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Breast cancer is the most common cancer among women worldwide. Breast cancer is caused by the overexpression of genes that facilitate breast cell proliferation. Estrogen receptor alpha (ER[Formula: see text]) mediation is mostly responsible for the development of malignant tumors by regulating the transcription of various genes as a transcription factor. ER[Formula: see text] is regarded as an important receptor for the proliferation of this disease and its inhibition is necessary for the treatment of breast cancer. In our study, the aim is to find out potential inhibitors for ER[Formula: see text] by docking 100 anticancer constituents of different halogen-based derivatives against ER[Formula: see text]. Among the 100 [Formula: see text]-based derivatives, 20 ligands were selected based on the interaction energy ranging from [Formula: see text]6.7[Formula: see text]kcal/mol to [Formula: see text]8.2[Formula: see text]kcal/mol and lower values of inhibition constant (0.92–11.77[Formula: see text][Formula: see text]). We have performed a comprehensive analysis of five most popular ligands (L17, L57, L61, L67, and L70) among these 20 selected derivatives. The interaction analysis is mainly stabilized by making different interactions including hydrogen bonding, hydrophobic, electrostatic, and halogen bonding with the active site of ER[Formula: see text]. A quantum study based on frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), and global chemical reactivity descriptor (GCRD) is carried out to explore the structural chemistry of our most popular ligands which indicates that they are quite reactive and kinetically stable. Additionally, we also assess the ADMET profiles to predict the toxicity and drug-likeness of our lead compounds. Our selected ligands have the highest absorption and good clearance rate and have no AMES toxicity, skin sensitization, and hepatotoxicity. Molecular dynamics simulations were run to check the conformational stability of apo form of ER[Formula: see text] and complex state, at 60-ns time scale. The molecular dynamics simulations are based on the plots of RMSD, RMSF, [Formula: see text], SASA, and the number of H-bonds. The results of RMSD and RMSF showed that the lead compounds L17, L57, L61, L67, and L70 are most stable and have no significant residual fluctuations and deviation. The analysis of the plots of [Formula: see text], SASA, and the number of H-bonds revealed that the complexes L17, L57, and L70 are most stable. So, the lead anticancer compounds L17, L57, L61, L67, and L70 are the most promising inhibitors against ER[Formula: see text] of breast cancer. The comprehensive analysis of all studied parameters highlighted that our selected ligands have great potential to inhibit ER[Formula: see text]. So, it can be concluded that the selected halogen-based derivatives can promote rational drug design for the target therapies of ER[Formula: see text] of breast cancer.

The narrow bandgap PbSe has attracted a remarkable interest from the researchers in recent years for their potential optoelectronics and photovoltaic applications. In this article, we report the optoelectronic properties of cubic (NaCl-type) and orthorhombic (Cmcm- and Pnma-type) polymorphs of PbSe using the density functional theory based first-principles approaches. In accordance with the available literature, the NaCl–PbSe has been found stable in the ground state, whereas the Cmcm-, Pnma-types of PbSe have been realized at intermediate pressure of ~4.5 GPa. The electronic structures and optical spectra of these polymorphs have been determined using the Tran-Blaha modified Becke-Johnson exchange potential with and without spin-orbit coupling (SOC) effects. The inclusion of SOC has shown important effects on the electronic structures and consequently on the optical spectra. Despite SOC driven energy gap narrowing of these polymorphs, the direct bandgap nature of Cmcm-PbSe calculated with TB-mBJ has changed to indirect nature with the inclusion of SOC. Moreover, our results of the optical spectra of NaCl–PbSe have shown that this phase is isotropic, whereas a sufficiently high degree of anisotropy in the optical spectra has been recorded for Cmcm-, Pnma-types of PbSe. These PbSe polymorphs exhibited a high optical absorption that approaches as large as 106 cm−1. Moreover, our study provides comprehensive details of exciton binding energies and plasmon energies. This work is believed to provide a strong foundation to exploit the optoelectronic character of the studied phases of PbSe for next-generation optoelectronic and photovoltaic applications.

Present investigation deals with an in depth study of three compounds including 4-(4-chlorophenyl)-8-methyl-2-oxo- 1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile (1), 4-(4-bromophenyl)-8-methyl-2-oxo-1,2,3,4,4a,5,6,7-octahydroquinoline-3- carbonitrile (2) and 8-methyl-2-oxo-4-(thiophen-2-yl)-1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile (3) with respect to their structural, electronic, optical and charge transport properties. The ground and excited states geometries were optimized by density functional theory (DFT) and time dependent DFT, respectively. To rationalize the adopted methodology, the calculated geometrical parameters at ground state were compared with the experimental crystal structures. Several quantum chemical insights including the analysis of frontier molecular orbitals (FMOs), total/partial density of states (T/PDOS), molecular electrostatic potentials (MEP), local and global reactivity descriptors revealed that the studied compounds would be efficient multifunctional materials. The absorption wavelengths as well as their major transitions were thoroughly studied at TD-B3LYP/6-31G** level of theory. The smaller hole reorganization energies indicate that all these compounds might show better hole transport tendency. The anionic geometry relaxation of compound 2 is larger than the cationic form which leads to higher electron reorganization energy revealing the reduction of electron charge transport as compared to the hole.

Breast cancer (Bca) causes the highest rate of mortality in females owing to the out-of-control cell division in breast cells. In this work, we perform an in-silico screening based on molecular docking and molecular dynamic of curcumin derivatives against ERα. In this study, we carry out, molecular docking of fifty (50) curcumin derivatives having anticancer potential by using virtual screening tools. Ten (10) ligands were selected based on binding energy ranged from (-7.4 kcal/mol to -9 kcal/mol), lower values of inhibition constant (0.23µmol to 3.59µmol), and visualisation of intermolecular interactions. Additionally, we also assess ADMET properties of selected ligands for prediction of their toxicity and drug-likeness. The molecular dynamic simulations (MD) including RMSD, RMSF, Rg, SASA, number of H-bonds and MM-PBSA binding free energy results showed that ligand L2 and L8 bind to estrogen protein ERα more proficiently with good stability over 120 ns. These results suggest lead anticancer compounds L2 (Salicylidenecurcumin) and L8 (Curcumin difluorinated) are the most promising inhibitor against ERα of Bca with ∆Gbind values of (-2.939 and -4.369) kcal/mol. we expect that our findings will evoke the scientific community to further do in-vitro and in-vivo investigations for screened curcumin derivatives against ERα of Bca.

The current investigation applies the dual approach containing quantum chemical and molecular docking techniques to explore the potential of benzothiadiazole (BTz) and its derivatives as efficient electronic and bioactive materials. The charge transport, electronic and optical properties of BTz derivatives are explored by quantum chemical techniques. The density functional theory (DFT) and time dependent DFT (TD-DFT) at B3LYP/6-31G** level of theory utilized to optimize BTz and newly designed ligands at the ground and first excited states, respectively. The heteroatoms substitution effects on different properties of 4,7-bis(4-methylthiophene-2yl) benzo[c] [1,2,5]thiadiazole (BTz2T) as initial compound are studied at molecular level. Additionally, we also study the possible inhibition potential of COVID-19 from benzothiadiazole (BTz) containing derivatives by implementing the grid based molecular docking methods. All the newly designed ligands docked with the main protease (MPRO:PDB ID 6LU7) protein of COVID-19 through molecular docking methods. The studied compounds showed strong binding affinities with the binding site of MPRO ranging from −6.9 to −7.4 kcal/mol. Furthermore, the pharmacokinetic properties of the ligands are also studied. The analysis of these results indicates that the studied ligands might be promising drug candidates as well as suitable for photovoltaic applications.

The current work is to spotlight the key structure-property features of a novel thiourea complex bis(thiourea) silver(I) nitrate (BTSN) for future applications in nonlinear optical devices through dual approach involving experimental and theoretical techniques. The synthesis and growth of good quality single crystals of a relatively new material BTSN have been done. The crystal structure, quantitative and qualitative, vibrational, optical and dielectric analysis of the grown single crystals was carried out. The optical transparency of the grown crystals is found to be more than 80% confirms its colorless nature and applications in optoelectronic devices. Further, the state-of-art computational methods have been applied to obtain the ground state molecular geometry at B3LYP/6-31G∗, MP2/6-31G∗ and M06/6-31G∗ levels of theory. Various key electro-optical properties (complementary to experimental results) such as IR, Raman, and polarizabilities have been determined at the same levels of theory. The static and dynamic polarizability and first hyperpolarizability both were calculated to comprehend the potential applications of BTSN in nonlinear optics. In addition to the above, numerous novel molecular level insights have been achieved in the form of total and partial density of states, HOMO-LUMO gap and molecular electrostatic potential map. The calculated values of static and frequency dependent dynamic first hyperpolarizability are found to be 8.46 × 10−30 and 2.30 × 10−30 esu which are about 23 times and 13 times greater than those of prototype urea molecule, respectively, calculated at the same B3LYP/6-31G∗ level of theory. From the analyzed results it is clear that the titled compound possesses excellent electro-optic properties that make it a decent contestant for photonic devices. Keywords: Crystal growth, Optical properties, Nonlinear optical material, Density functional theory

The single-layered Germanium sulfide exhibits interesting optoelectronic properties however the indirect bandgap hinders its practical applications for nanoscale optoelectronic and photovoltaic devices. Herein, we report two direct bandgap polymorphs of single-layered GeS (δ-GeS and e-GeS) and explore their optoelectronic properties using the density functional theory based computational approaches. The indirect bandgap of the intrinsic GeS monolayer (α-GeS) calculated in present study amounts to 0.76 eV, whereas the direct bandgap energies for δ- and e-derivatives of GeS have been recorded as 1.93 and 2.10 eV respectively. The optical spectra of these monolayers demonstrated a high degree of anisotropy and significantly different optical absorption, reflection, and refraction coefficients were seen in the x- and y-directions. They exhibited different plasmons energies along x- and y-directions which reveal the GeS monolayers as potential polarizers of electromagnetic radiations. Moreover, these monolayers demonstrated exceptionally large optical absorption spanning over a wide range of electromagnetic spectrum. The absorption coefficients were recorded typically larger along y-axis than x-axis. The designed direct bandgap monolayers are believed to overcome the major hurdles of single-layered GeS for nanoscale optoelectronic applications.

Donor–bridge–acceptor (D–π–A) compounds have garnered significant attention, and have led to increased efficiency of photovoltaic devices. In this study, an effective D–π–A dye (TPA-PT) was designed that contains tri-phenyl-amine, thiophene-pyrimidine and cyanoacetic acid as donor (D), π-bridge and acceptor (A), respectively. The TPA-PT was adsorbed on the semiconductor surfaces, i.e., Ti3O6H and Ti6O12H clusters, and light was shed on the adsorption behavior by bidentate bridging @Ti3O6H and chelating @Ti6O12H modes. The frontier molecular orbitals (FMOs) and structural and optical properties are studied by applying density functional theory (DFT) and time-dependent DFT (TD-DFT). Important parameters including charge transfer mechanism, electronic coupling constants (|VRP|), band alignment, electron injection (ΔGinject), relative electron injection (ΔGrinject) and light-harvesting efficiency are comprehensively investigated. The charge transfer from TPA-PT dye to the semiconductor surface of Ti3O6H and Ti6O12H clusters is explored as well. Additionally, the computed values of open-circuit photo-voltage (Voc) are presented for two cases of TiO2 and PCBM.

In the current study, the 2,6-diphenyl-4-(3,4,5-trimethoxyphenyl)pyridine (compound 1) has been investigated as proficient material for optoelectronic and nonlinear optical (NLO) applications. In order to highlight the potential at both solid-state (bulk) and molecular levels, different electronic and optical parameters were investigated. The optical and electronic parameters such as refractive index, reflectivity, dielectric function, extinction coefficient, conductivity, electronic band structure, density of states (DOS) of newly reported trimethoxy-phenylpyridine at bulk (solid-state) level have been studied. The band gap is found to be 2.817 eV, which revealed the photon absorption competency has been improved in compound 1 due to narrow band gap and has the capability of containing the absorbed energy. Other calculated optoelectronic properties also revealed that the compound 1 might be better for semiconductor applications. Additionally, the geometric parameters, polarizability (isotropic and anisotropic) and third-order NLO polarizability have been computed at molecular level. For compound 1, its isotropic and anisotropic values are found to be 63.41 × 10−24 esu and 46.22 × 10−24 esu, respectively. The calculated γ amplitude for studied material has been computed as 187.53 × 10−36 esu that is about 25 times bigger than that of the γ amplitude for pNA (a prototype NLO molecule). The third order NLO response for compound 1 has been further tuned through the designing of its further derivatives in the form of compounds 1a, 1b and 1c. Thus, the present study highlights the important optoelectronic and NLO properties of compound 1 and its derivatives.

Multifunctional pyrazole derivative, i.e. 3-amino-1-(5-hydroxy-3-methyl-1H-pyrazol-4-yl)-1H-benzo[f]chromene-2-carbonitrile (PBCC) has been synthesized and characterized. To shed light on various properties of interests, the ground state geometry was optimized by adopting Density Functional Theory (PBE/TZ2P). The effect of different functionals on the absorption wavelengths was studied by using Time-Domain DFT (TDDFT), e.g. GGA functional PBE, hybrid functionals B3LYP and PBE0, rang separated functionals CAM-B3LYP, LCY-PBE and CAMY-B3LYP, Dispersion Corrections PBE-D3 and B3LYP-D3. Among all these functionals PBE and PBE-D3 were found to be good choices which reproduced the absorption spectra of the PBCC. With the aim to enhance the electro-optical, charge transfer and photovoltaic properties, five new derivatives were designed by di-substituting the –F, –Cl, –Br, –COOH and –CN at benzochromene moiety. The electron injection barrier, band gap alignment and related calculated photovoltaic parameters revealed that PBCC and its newly designed derivatives would be proficient to be used in photovoltaic devices. These compounds can be used as donor materials in dye-sensitized solar cells (DSSCs) with favorable type-II band alignment. Moreover, PBCC and most of its derivatives might also be good choice as efficient acceptors with poly(dithieno[3,2-b:2,3-d]pyrrole thiophene) (PDTPr-T) and donor materials with Phenyl-C61-butyric acid methyl ester (PC61BM) in organic solar cells.

The field of point particle dynamics is correlated with the study of particle dynamics around the black hole and one can initiate the study of a more complex motion of extended/celestial bodies. In this article, we consider the study of the dynamics of the neutral/charged particles around the quantum corrected-Schwarzschild black hole and Schwarzschild black hole. We investigate Noether symmetries and their conservation laws corresponding to the quantum corrected-Schwarzschild spacetime. We also study the effect of angular momentum, quantum parameters and magnetic field on the dynamics of neutral and charged particles around the quantum corrected-Schwarzschild black hole and Schwarzschild black hole.

The graphene nanoribbons (GNRs) have been established for device applications in numerous fields due to their superb electro-optical properties. GNRs are used in many nanoscale electronic devices, e.g., solar cells, semiconductors, field effect transistors and nonlinear optics. The isolated molecule precursor of boron doped GNR parent compound 5,10-bis(10-bromoanthracene-9-yl)-5,10-dihydroboranthrene (Br-GNR) and its newly designed derivatives 5,10-bis(10-fluoroanthracene-9-yl)-5,10dihydroboranthrene (F-GNR) and 5,10-bis(10-chloroanthracene-9-yl)-5,10dihydroboranthrene (Cl-GNR) were optimized using density functional theory (DFT) at PBE0/6-311G* level. By replacing the –Br by –F atoms in Br-GNR, the ionization potential (IP) and electron affinity (EA) declined. The hole and electron reorganization energies (λ(h)/λ(e)) of halogenated doped GNRs has been systematically compared with some standard hole and electron transfer materials. The smaller λ(h) values are showing that the studied compounds would be superior hole transfer candidates. The density of states and optical properties at bulk level (including dielectric function, refractive indices, conductivity and loss function) have been probed. The polarizability (γ) amplitudes of F-GNR, Cl-GNR and Br-GNR are 34, 21 and 22 times larger than that of para-nitroaniline at same PBE0/6-311G* level. The calculated non-linear optical (NLO) polarizability amplitudes, optoelectronic and charge transfer properties showed that all the compounds would be good contenders for NLO and semiconductor devices.

The low cost, highly stable and earth abundant furan-based small molecules have been recognized to be prospective and innovative organic semiconductor materials (OSMs) for optoelectronic applications. In this article, we explore various optoelectronic properties of conjugated isomers containing bifuran (TFFT) and bithiophene (FTTF) by employing the density functional theory (DFT) based ultrasoft pseudopotential approach. Our investigations specify the TFFT as a wide and direct bandgap semiconductor with bandgap value of 2.00 eV. Whereas, the bandgap of FTTF is found to be reduced by 0.239 eV in comparison with TFFT owing towards the effect from p-orbitals of carbon and sulfur atoms present at the center of molecular crystal structure. The reduction in the energy and the density of states (DOS) for the compounds in current study endorsed that bandgap could be tuned to any desired value for optoelectronic applications through derivatives designing. Moreover, the achieved outcomes for optoelectronic parameters like dielectric function, conductivity, refractive index, reflectivity, extinction coefficient and energy loss function validates their suitability to use them in electro-optical devices.

Ternary copper sulphides, especially copper-bismuth-sulphide (Cu-Bi-S), are alternative solar absorber materials due to their earth-abundant and non-toxic constituent elements, compared to the conventional copper indium gallium sulphide and cadmium telluride films. In this study, Cu-Bi-S thin films were deposited onto soda lime glass substrates using a one stage co-evaporation process from Cu2S and Bi2S3 sources, with the deposition temperatures varied from room temperature to 400 °C. X-ray diffraction analysis confirmed that Cu3BiS3 was the dominant phase in the Cu-rich films, and the crystalline quality of the films was significantly improved with increasing the deposition temperature. An optical bandgap of 1.4 eV was achieved for the film deposited at 400 °C, which demonstrated a Hall mobility of 3.95 cm2/V-s and a carrier concentration of 7.48 × 1016 cm−3. Cu3BiS3 films deposited at 375 and 400 °C were implemented into superstrate solar cell structures (glass/ITO/n-CdS/p-Cu3BiS3/Al).

In the present work structural and optoelectronic properties of alkali niobates ANbO3 (A = Na, K and Rb) are investigated in different crystal structures e.g. cubic, tetragonal, orthorhombic and rhombohedral using generalized gradient approximation (GGA), GGA with Hubbard potential (GGA + U) and modified Becke-Johnson (mBJ) approach. Structural properties show that ferroelectric rhombohedral crystal structure is the most stable structure of these compounds. The anti-ferroelectric and paraelectric are their higher energy crystal structures. The obtained results of the electronic band gaps show that mBJ is the appropriate exchange-correlation approximation for the calculations of electronic and optical properties of these niobates. They are indirect band gap semiconductors, except the ferroelectric rhombohedral and antiferroelectric orthorhombic NaNbO3. The valence band is predominantly contributed by O 2p orbitals and conduction band is made of Nb 4d orbitals. Real and imaginary parts of dielectric function and other optical parameters such as energy loss function, sum rule and refractive index are also investigated.

The low-cost and non-toxic candidates of the Group-IV monochalcogenide family have attracted significant attention in recent years for large-scale thermoelectric applications. We conduct comprehensive investigations of the thermoelectric response of relatively inexpensive and less toxic cubic structured Si-monochalcogenides (π-SiS, π-SiSe, and π-SiTe) for renewable energy applications. The full-potential linearized-augmented-plus-local-orbital method within density functional theory has been adopted to calculate the ground state energies, whereas the semi-classical Boltzmann transport theory has been used for the calculations of thermoelectric properties. The Si-monochalcogenides in cubic phase demonstrate large values of thermopowers that amounts to 1740.0 μV/K, 1405.0 μV/K, and 771.92 μV/K of the π-SiS, π-SiSe, and π-SiTe respectively at 300 K. The thermopowers show an insignificant response to increase in temperature which is beneficial for the high-temperature thermoelectric applications of these materials. The optimal values of thermoelectric power factors of the cubic structured Si-chalcogenides occur at attainable doping levels and have been originated from the joint contribution of moderate electrical conductivities and thermopowers. These materials demonstrate the figure of merit values approaching unity and have shown a trivial response to the temperature gradient. Moreover, the occurrence of the optimal values of thermoelectric coefficients for electrons doped regime suggests the n-type doping as an easy option for enhancing the thermoelectric performance of these materials. Our investigations show that the Si-monochalcogenides in cubic phase feature interesting thermoelectric performance and can be used as a suitable replacement for the toxic and expensive binary chalcogenides for thermoelectric applications.

Cesium halide double-perovskites (Cs2AgCrX6; X = Cl, Br, and I) have been investigated for potential applications in optoelectronic devices. Density functional theory (DFT) has been utilized to study the structural, chemical bonding, electronic, mechanical, optical, and thermoelectric properties of these materials. Structural analysis has revealed that these compounds favor a face-centered cubic double-perovskite crystal structure with space group Fm-3m. The electronic properties show that Cs2AgCrX6 (X = Cl, Br) are indirect whereas Cs2AgCrI6 is a direct band-gap semiconductor, and their band-gap values are 2.81, 2.1, and 0.9 eV, respectively. The bonding nature between Ag-X and Cr-X atoms is covalent, while ionic bonds exist between Cs-X atoms. The systems are good dielectric materials and have the potential to be used in optoelectronic devices. Post-DFT calculations have been performed to calculate thermoelectric parameters. The increase of the Seebeck coefficient in these materials with temperature up to 400 K satisfies the Mott formula. Above this temperature, thermal excitations of extrinsic carriers decrease the Seebeck coefficient. The mechanical properties of these compounds indicate that they are ductile and anisotropic.

The nonlinear optical (NLO) and antiviral properties of naphthalimide Schiff base compounds (5a–c) were experimentally and computationally investigated. The synthesized compounds (5a–c) were successfully characterized via UV–Vis, FTIR, 1H NMR, fluorescence spectroscopy, and elemental analysis. The calculated average third-order NLO polarizabilities (˂γ˃) of 5a, 5b, and 5c were found to be 5, 9, and 21 times greater than the ˂γ˃ amplitude of p-NA, respectively. The computed results revealed the potential of the synthesized compounds for NLO applications. Additionally, molecular docking studies of the synthesized compounds with two crucial SARS-CoV-2 proteins were performed to examine their biochemical properties. Compound 5c exhibited a higher binding affinity with the spike protein compared to that with Mᴾᴿᴼ. The results obtained herein indicate the potential of the synthesized naphthalimide derivatives for optoelectronic and drug design applications.

In this study, three chalcone derivatives with a basic skeleton of [1,100-biphenyl]-4-yl)-3-(3-nitrophenyl)prop-2-en-1-one are investigated. The basic skeleton was modified with the addition of three-terminal groups including hydrogen (1), methyl (2), and methoxy group (3). Using CASTEP Module, the optoelectronic properties are evaluated. The solid-state geometries of these systems are explored within the periodic boundary conditions (PBC). Among these systems, system 3 is found much better in terms of electron transport and optical properties such as dielectric function, absorption, conductivity, reflectivity, loss function, and refractive index. System 3 showed a higher dielectric function value about 3.7 at 1.8 eV thereby absorption 6.9 × 104 cm−1 at 300 nm and conductivity 1.2 fs−1 at 3.5 eV in the (0 0 1) plane. Furthermore, system 3 exhibited a high reflectivity and loss function in the (0 1 0) plane. Electronic band structure, the density of state, and electronic coupling analysis also reveal that system 3 has a potential application in charge transport devices. The study of electronic couplings that dominate the slowest electron hopping in a potential conductive path is roughly four to ten times larger for the holes than for the electrons. The transport pathways in systems 1 and 2 are 2D, while 1D in system 3. The bottleneck rate for electron transport is expected to be ~25 faster for system 3 than the other systems. This system 3 shows an excellent potential both at molecular and bulk levels for efficient charge transport material.

Two new anthracene derivatives donor–π–acceptor (Compound 1) and acceptor–π–acceptor (Compound 2) have been designed with the aim to understand the effect of donor and acceptor on the electronic, optical and charge transfer properties of sensitizers and sensitizers@TiO2 cluster. The electron donating group (–OH) and acceptor (–COOH) have been substituted at periphery and the effect was studied thoroughly. The ground state geometries of both the compounds were optimized by using density functional theory (DFT) at B3LYP/6-31G**, CAM-B3LYP/6-31G** LC-BLYP/6-31G**, BHandHLYP/6-31G** and PBE1PBE/6-31G** levels of theory. Moreover, ground state geometries of sensitizers@TiO2 cluster were optimized by adopting the same methods along with LANL2DZ pseudopotential for Ti while 6-31G** basis set for all other atoms. The electro-optical properties and charge transfer nature of dye adsorbed at TiO2 cluster were also systematically investigated. The absorption spectra of anthracene derivatives before and after adsorption at TiO2 cluster were limelighted by adopting time dependent DFT.

With the aim to tune the optoelectronic, charge transport and nonlinear optical properties, four novel star shaped compounds were designed from the initial structure 4,6-di(anthracenothiophen-2-yl)pyrimidine (DATP). The (2,5-di-(thiophen-2-yl)-4,6-di-(anthracenothiophen-2-yl)pyrimidine) (1), (2,5-di(benzo-thiophen-2-yl)-4,6-di-(anthracenothiophen-2-yl)pyrimidine) (2), 2,5-di(naphthothiophen-2-yl)-4,6-di-(anthracene-thiophen-2-yl)-pyrimidine (3), and 2,4,5,6-tetrakis(anthracene-thiophen-2-yl)pyrimidine (4) were deliberated by substituting the thiophene, benzothiophene, naphthothiophene and anthracenothiophene moieties at positions 2 and 5 of the pyrimidine unit in DATP, respectively. The ground and excited state geometries were optimized by adopting the density functional theory (DFT) and time-dependent DFT at B3LYP/6-31G** and TD-B3LYP/6-31G** level of theories, respectively. We shed light on the energies of the frontier molecular orbitals (FMOs), energy gaps (Egaps), absorption, fluorescence, total/partial density of states (T/PDOS), molecular electrostatic potentials (MEP) and non-linear optical (NLO) properties. The comprehensible intra-molecular charge transport has been noticed from side wings to the electron-deficient central core at both the ground and excited states. The increment in the wings length increases the electron affinity, reduces the ionization potential and lowered the hole reorganization energy. The higher electron affinity and smaller hole reorganization energy values revealed that newly designed materials might be thermodynamically more stable with enhanced intrinsic hole mobility.

Using the first principles calculations, optical and nonlinear optical (NLO) properties are calculated for three crossed shaped chromophores having alike benzoic acid π-conjugated side chains but different central cores i.e. phenyl in 1-Ph , pyrazino[2,3- g ]quinoxaline in 2-PyQ and tetrathiafulvalene in 3-TTF . Molecular geometries are effectively reproduced and compared to their experimental crystallographic structures. The third-order NLO polarizability is calculated with three different DFT functionals including M06, PBE0 and B3LYP using 6-311G* basis set. Our calculated third-order NLO polarizability amplitudes and their comparison to those of standard and contemporary NLO chromophores indicate that all the three compounds have remarkably larger NLO response. The γ amplitudes of compounds 1-Ph , 2-PyQ and 3-TTF are 429.6 × 10 −36 , 1871.7 × 10 −36 and 967.5 × 10 −36 esu, respectively, at M06/6-311G* level of theory. Interestingly, in present investigation the γ amplitude of the best-studied NLO compound 2-PyQ is 257 times larger than that of para nitroaniline (7.279 × 10 −36 esu) at the same M06/6-311G* level of theory. The TD-DFT calculations are used to trace the origin of larger NLO response. Additionally, total and partial densities of states are calculated to compare the effect and contributions of central cores in all adopted compounds. Thus, the present investigation will not only highlight the NLO potential of entitled compounds but also provoke the interest of experimentalists to effectively modify the central cores for such other applications.

Owing to their excellent electrochemical properties, graphenes found applications in several fields ranging from semiconductors, solar cells, field effect transistors, and nanoscale electronic devices as well as in nonlinear optical (NLO) applications. The structural features, electro-optical, charge transport and nonlinear optical properties of the boron-doped graphene (BG) compound 1 were studied using density functional theory methods The BG compound comprises a central electron deficient site of boron atoms, which can serve as electron acceptor while terminal alkoxy groups as donors leading to powerful donor-π-acceptor (D-π-A) configuration. The experimental crystal structure was successfully reproduced by optimized ground state geometry at PBE0/6-311G* level of theory for isolated molecule. The experimental lattice parameters, geometries, crystal presentation and alignment of molecules in the unit cells as well as their packing orientation of BG compound 1 was also efficiently reproduced by applying periodic boundary conditions (PBC) at PBE level. The comprehensive intramolecular charge transfer (CT) was realized from terminal rings of the HOMO to the electron deficient sites of boron atoms of the LUMO. The nature of BG compound 1 might be more towards hole transport even though its hole reorganization energy is twice than that of the electron one due to the significant higher hole transfer integral values. The superior hole transfer integrals and intrinsic mobility values of the BG compound 1 might lead remarkable hole transport contender as compared to many other organic materials. The narrow band gap, density of states profile, dielectric function, uniform conductivity functions and noteworthy electronic as well as CT properties revealed that the BG compound 1 might be proficient optoelectronic contestant having intermolecular CT as well as intramolecular CT with optimal stability. A comparison of static third-order polarizability of BG compound 1 , as calculated in present investigation, was also performed with some standard NLO molecules as well as graphene nanoflakes. Moreover, longitudinal component γ zzzz of parent compound has been found 12 and 4 times larger than those of previously reported open-shell poly aromatic hydrocarbons (PAH). Interestingly, by increasing the donor ability, i.e., introduction of C 2 H 2 PhNH 2 groups in place of OC 4 H 9 groups (BG compound 3 ) at terminal positions boosts the amplitude ∼ 8 times than that of its parent BG compound 1 .

In the present study, we use the state of art density functional theory (DFT) techniques to calculate the structural, optoelectronic and nonlinear optical (NLO) properties for two novel chalcone derivatives. The geometrical structures of chalcone derivatives compound 1 and 2 are optimized using periodic boundary conditions (PBC) in solid-state phase as well as isolated single molecular geometry in the gas phase. The reasonable agreement is found among experimental, solid-state and gas phase single molecular geometries, which provide us, further confidence to explore the potential of above-entitled derivatives as good functional materials for electro-optical applications. For instance, the frequency dependent real parts of dielectric functions are calculated for compound 1 and 2. The maximum value of real part of the dielectric function for compound 1 and 2 at 0 eV are computed as 4.35 and 6.68 for the polarization vectors of (001) directions, respectively, which reveals the fact that the compound 1 and 2 might be good charge transport materials. The reflectivities of the compound 1 and 2 are 0.64 and 0.45 revealing that the compound 2 might be more efficient material for organic photovoltaic (OPV) applications. The results of the refractive index improved by doping the strong electron withdrawing groups (EWGs) shows that the compound 2 might be good refractor of the photon as compared to compound 1. The calculated values for static second-order polarizability are 3498 and 10464 a. u. and for frequency dependent second harmonic generations are 2557 and 6429 a. u. for compound 1 and 2, respectively, which indicates their significant potential for possible nonlinear optical applications.

The naphthalene is good contender which is intensively used in organic semiconductors. Here, three new naphthalene based compounds were prepared by the condensation of 1,5-diaminonaphthalene, 5-methylfurfural and 5-nitrofurfural. The prepared Schiff base compounds were analyzed by Fourier Transmission Infrared spectroscopy (FTIR), UV–vis spectroscopy (UV-vis) and single crystal x-ray studies. The compound 1 was obtained in P21/n crystal packing. A comprehensive electronic structure-property relationship was elucidated through the prism of frontier molecular orbitals (FMOs). The calculated absorption wavelengths at TD-B3LYP/6-31G** level displayed reasonably decent agreement to the experimental data. The effect of electron donating groups and electron withdrawing groups was discussed on optoelectronic properties, ionization potentials, electron affinities and reorganization energies. On the basis of transfer integrals and intrinsic mobility nature of the charge transport of compound 1 was discussed. The electron injection, electronic coupling constant and light harvesting efficiency revealed that the studied Schiff base compounds would be good contestants to be used in dye-sensitized solar cells. Compounds 2 and 3 have 8 and 6 times larger βtot than that of para-nitro aniline revealing that these materials might be good for nonlinear optics as well.

In the present quantum chemical investigation, for the first time, we shed light on the promising structure, charge transport and nonlinear optical properties (NLO) of oxygen-bridged planarized 4-aminopyridine (APY3O3). Density functional theory (DFT) and time dependent DFT methods are used to elucidate the novel structure, optical and NLO properties of open 4-aminopyridine (APY3) as well as oxygen-bridged closed APY3O3 systems. The calculated third-order polarizability 〈γ〉 for APY3 and APY3O3 is found to be 76.85 and 89.16 × 10−36 esu with the B3LYP method and the 6-311G** basis set, respectively, which is ∼10 and 12 times larger than that of para-nitroaniline (a prototype NLO molecule). Calculation of the electron affinity and reorganization energy suggests that good electron transfer properties are feasible by changing the geometry from open APY3 to closed APY3O3 through oxygen bridging. Interestingly, the configuration of a dimer having APY3O3 and oxygen-bridged triphenylborane (TPBO3) monomers demonstrates remarkable enhancement in NLO response through a novel non-covalent intermolecular charge transfer process. The present investigation not only evokes scientific interest regarding the promising structure of APY3O3 but also highlights its several optical and NLO properties that can be beneficial for its use as an advanced functional material in modern hi-tech applications.

The prospective of nitrogen doped graphene (NDG) as useful nonlinear optical (NLO) and charge transport materials is explored using first principles methods. A dual methodological strategy is adopted by performing molecular level and bulk level calculations through first principles methods. The calculated molecular geometry and absorption wavelengths are found to be in reasonable agreement with experimental results of parent NDG compound 1 (di-peri-(tert-butylbenzo)-di-peri-(tri-methoxybenzo)-di-peri-(pyrimidino)-coronene). Similarly, first principles calculations of the solid-state crystal structure show that NDG compound 1 retains a value of 1.585 eV as its direct band gap, which is potentially useful for a direct bad gap semiconductor for optical device applications. The calculation of second- (β) and third-order (γ) nonlinear optical properties indicates that compound 1 possesses reasonably large values of βtot (22.96 × 10−30 esu) and 〈γ〉 (238.53 × 10−36 esu) amplitudes, which may fall well within the figure of merit for second harmonic generation (SHG) and two-photon absorption (TPA) applications, etc. TD-DFT calculations along with the plots of the frontier molecular orbitals show an intramolecular charge transfer from the rest of the graphene fragment to the pyridine moieties (N-doped sites) accompanied by significant oscillator strengths for involved transitions in the absorption spectra. Additionally, several key optical parameters (dielectric and conductivity functions, refractive index and extinction coefficients) are calculated to assess the overall optical efficiency of parent NDG compound 1. The present investigation not only features the substantial potential of NDG compound 1 as an efficient optical material but also highlights the importance of the substitution of its terminal groups to enhance the first- and second hyperpolarizability amplitudes, as exemplified through the design of compound 3.

Pyrazole compounds are gaining noteworthy attention in our daily life from better biological active to the semiconducting materials. Present work deals in depth study of indigenously synthesized pyrazole compound, i.e., 2-[(3,5-dimethyl-1-phenyl-1H-pyrazol-4-yl)methylidene]indan-1,3-dione ( DMPI ) with respect to the structural, electronic, optical and charge transport properties. The ground and excited state geometries were optimized by applying density functional theory (DFT) and time dependent DFT, respectively. The frontier molecular orbitals (FMOs) have been spotlighted. The comprehensible intra-molecular charge transfer (ICT) from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) was observed. The absorption and emission wavelengths were studied at the TD-B3LYP/6-31G** level of theory. The total and partial density of states (T/PDOS) has been studied to understanding the contribution of different states in the electronic properties. The ionization potentials (IP), electron affinities (EA), reorganization energies, transfer integrals, intrinsic mobility and structure-property relationship have been discussed intensively. The smaller hole reorganization energy and superior transfer integral values resulting improved hole intrinsic mobility than the electron ones is revealing that DMPI would be better hole transport material.

The current work is focused to study the various of Dibromobis( l -proline) zinc(II) by Hartree–Fock and Density functional theory using 6-31G * and 6-311++G ** basis sets to spotlight its properties at molecular level. The observed wavenumbers and geometrical parameters such as bond lengths and bond angles are found to be in agreement with experimental reports. The values of μ tot and β tot calculated at B3LYP/6-31G* level of theory are found to be 4 and 16 times higher than urea. The electronic properties such as absorption wavelength, excitation energy and frontier molecular orbital energies are performed by time dependent DFT approach. The absorption wavelength calculated at TD-DFT/B3LYP/6-311++G** level of theory is observed at λ exc = 285 nm (4.357 eV) and found in semi quantitative agreement with the experimental value (300 nm), which is assigned as ligand metal charge transfer. The global reactivity descriptors and molecular electrostatic potentials were also calculated and discussed. The high value of dipole moment and first hyperpolarizability suggest that the titled compound is an excellent material for optoelectronic device applications.

Using the computational techniques, the cubic structure of spinel sulfides Sc2XS4 (X = Zn, Mg, and Be) were investigated for electronics, structural and optical properties. We evaluated the lattice parameter “a”, total density of state (DOS) and optical properties by the full-potential linearized augmented plane wave (FP-LAPW) method within the background of density functional theory (DFT) through the generalized gradient approximation (GGA). The Trans-Blaha modified Becke Johnson (TB-mBJ) potential approximation has been utilized to calculate the electronic bandgap as it is considered a good approach to reproduce the energy gap more accurately. The profile of electronic band structures disclosed the direct bandgaps of the magnitude 1.62, 2.30, and 1.60 eV for Sc2ZnS4, Sc2MgS4, and Sc2BeS4, respectively. Similarly, these materials display decent absorption and reflectivity in the UV region of light revealing the potential of these spinal sulfides as a shield against UV radiations. Our computed results of electronic and optical properties recommend that the studied spinel sulfides Sc2XS4 (X = Zn, Mg, and Be) would be suitable for photovoltaic and solar cell applications.

Zkoumání materiálů s vysokou účinností pro příští generace optoelektronických a fotovoltaické aplikace je velmi důležité. V tomto článku se budeme zkoumat potenciál nově navržených krychlových strukturované Siliconmonochalcogenides (π- SiS, π-SiSe, a π-SiTe) pro fotovoltaické a optoelektronické aplikace. Funkční teorie hustota byla přijata metoda založená na plný potenciál linearizovaný rozšířené rovině vlna a místní okružní (FP-L (APW + lo)) k provedení této studie. Tyto materiály mají soudržné a formace energie srovnatelný s ostatními stabilní binární chalkogenidů odrážejí jejich termodynamickou stabilitu v kubickou strukturu. Výsledky elektronických pásových struktur odhalit jim nepřímé bandgap materiály bandgap energie 1,09, 0,88 a 0,47 eV pro π-SiS, π-SiSe, a π-SiTe v tomto pořadí. Tato nová třída monochalcogenides bylo zjištěno, bohatý na několik zajímavých vlastností, jako je velké hustoty stavů kolem Fermiho úrovni, relativně ploché valence a pásma vodivosti hran a těžších mas nosičů náboje. Výsledkem je, že bylo pozorováno vysoké absorbance světla (~106 / cm) ve viditelné a spodní ultrafialové (UV) oblasti. Podobně, vhodné optické odrazivosti ve vyšší UV oblasti bylo zaznamenáno, které poukazuje na jejich potenciál pro použití jako ochrana proti UV záření. Tento článek se dále zabývá exciton vazebné energie, energie Plasmon je a nízko a vysokofrekvenční dielektrické konstanty těchto materiálů. Naše výsledky ukazují krychlových strukturované Simonochalcogenides jako termodynamicky stabilní a slibné materiály pro špičkové optoelektronických a fotovoltaické aplikace. Exploring the high-efficiency materials for next-generation optoelectronic and photovoltaic applications is of great importance. In this article, we explore the potential of the newly designed cubic-structured Siliconmonochalcogenides (π- SiS, π-SiSe, and π-SiTe) for photovoltaic and optoelectronic applications. The density functional theory based fullpotential linearized augmented-plane-wave plus local-orbital (FP-L(APW + lo)) method has been adopted to carry out this study. These materials possess cohesive and formation energies comparable to the other stable binary-chalcogenides reflecting their thermodynamic stability in the cubic structure. The results of electronic band structures reveal them indirect bandgap materials of bandgap energy 1.09, 0.88 and 0.47 eV for π-SiS, π-SiSe, and π-SiTe respectively. This new class of monochalcogenides has been found rich in several interesting features such as large density of states around the Fermi-level, relatively flat valence and conduction band edges, and heavier masses of charge carriers. As a result, the high absorbance of light (∼106/cm) in the visible and lower ultraviolet (UV) regions has been observed. Similarly, a suitable optical reflectivity in the higher UV region was recorded which highlights their potential for application as a shield against UV radiations. This article further addresses the exciton binding energies, plasmon's energies, and low and high-frequency dielectric constants of these materials. Our results demonstrate the cubic-structured Simonochalcogenides as thermodynamically stable and promising materials for cutting-edge optoelectronic and photovoltaic applications.

Effect of various electron donating amines, i.e., dimethylamine (DMA), diphenylamine (DPA), phenylnaphthylamine (PNA) and dinaphthylamine (DPA) at 6 position on the electronic, photophysical and charge transfer properties of 1,3-diphenyl-1H-pyrazolo[3,4-b]quinolone (DPPQ) as a parent molecule has been explored at the molecular and solid state bulk level. The effect of substituents on absorption and emission was studied at TD-B3LYP/6-31G** level in acetonitrile. The computed emission wavelengths were being red shifted for DMA-DPPQ, DPA-DPPQ, PNA-DPPQ than that of parent molecule which might be green, yellow, orange and red light emitters. The charge transfer nature of various DPPQ derivatives has been explored on the bases of ionization potential, hole extraction potential, electron affinity, reorganization energies, transfer integrals and intrinsic mobility. The DMA substitution at position 6 of DPPQ boost up the electron transfer integrals leading to balanced charge transport for holes and electrons. Moreover, total/partial density of states and optical properties (dielectric constant, extinction coefficient refractive indices, reflectivity and conductivity) at solid state bulk scale have been explored. Different properties of interest at molecular and solid state levels revealed that 1,3-diphenyl-1H-pyrazolo[3,4-b]quinolone derivatives would be efficient materials to be used in multifunctional organic semiconductor devices.

In the present study, the number and position of sulfur atoms on naphthalene diimide (NDI) is systematically investigated to tune its nonlinear optical (NLO) response properties. Our DFT calculations for third-order polarizability (γ) show that the thionation significantly influences the nonlinear optical property of NDI as it is seen among its several designed derivatives (NDI-1 to NDI-10). The smallest and the largest γzzzz amplitudes are 503.49 × 10−36 and 1299.5 × 10−36 esu for NDI-1 (having tetraone group) and NDI-10 (having tetrathione group), respectively. The increase in γzzzz amplitude for NDI-10 is 796 × 10−36 esu, which is ∼150% from the γzzzz amplitude of NDI-1. A comparison of the γzzzz amplitudes of our designed derivatives are made with para-nitroaniline i.e. a prototype NLO molecule. The γzzzz amplitude of pNA is found to be 42.64 × 10−36 esu at the same B3LYP/DZVP2 level of theory. Using two-level model, the origin of larger γzzzz amplitudes is traced in lower transition energy of NDI-10. Furthermore, the calculation of vertical ionization potentials (VIPs) shows that the thionation does not affect the stability of designed derivatives, where a slight difference of 0.06 eV is seen between the VIPs of NDI-1 (6.63 eV) and NDI-10 (6.57 eV). Thus, a systematic comparison of the third-order polarizability and other electro-optical properties of our designed derivatives shows that our derivative systems possess good potential for their practical realization in the field of optical and NLO materials.

Contrary to the enormous number of previous studies on carbon nanotubes (CNTs), herein, we realized the origin of the intrinsic open-shell diradical character and second hyperpolarizability γ using a broken symmetry approach. This study was inspired by our recent findings (S. Muhammad, et al., Nanoscale, 2016, 8, 17998 and Nakano, et al., J. Phys. Chem. C, 2016, 120, 1193). We performed structural modifications through a unique asymmetric donor-nanotube framework, which led to a novel paradigm of modified CNTs with tunable open-shell diradical character and remarkably superior NLO response properties. Interestingly, asymmetry and diradical character were found to be the crucial factors to modulate the second hyperpolarizability γ. We initially performed a comparative analysis of the diradical characters and γ amplitudes of boron nitride nanotubes (BNNTs) and CNTs possessing significant ionic characters and covalent characters, respectively. The basic findings for these simple configurations were further extended to the donor-acceptor CNT paradigm, which finally led to excellent asymmetric donor-CNT configurations with remarkably larger γ amplitudes. Furthermore, among the CNTs, finite length zigzag CNT(6,0)3 were modified with different donor-acceptor configurations. Interestingly, for the first time, unique donor-nanotube configurations [1,4-(NH2)2CNT-(6,0)3 and 1,4-(NH2)2CNT-(6,0)5] were found; they showed significantly robust γ amplitudes as large as 2519 × 103 and 4090 × 103 a.u. at the LC-UBLYP(μ = 0.33)/6-31G* level of theory. Additionally, several molecular level insights have been obtained for these novel donor-nanotube configurations using their odd electron densities, molecular electrostatic maps, densities of states and γ density analyses to highlight the realization of these novel materials for highly efficient optical and NLO applications.