Search

Abstract Imidazolium L-tartrate (IMLT) single crystal was grown using solution growth technique. The grown crystal belongs to monoclinic crystal structure with space group P2 1. Intermolecular interactions of IMLT is executed by the Hirshfeld surface analysis. The structure of the grown crystal was stabilized by an extensive network of O H⋯O, N H⋯O and O H hydrogen bonds. The vibrational modes are assigned based on potential energy distribution (PED). 13C and 1H NMR spectra were recorded to interpret the environment of the molecular structure. The HOMO-LUMO energy gap shows that the molecular chemical stability is high for the IMLT molecule. The Mulliken charge distribution confirms that the highest value is noted in C17, whereas the lowest value is obtained in C10 atom. The natural bond orbital (NBO) analysis has been computed to find out the electron delocalization and conjugative interactions. The bonding and anti-bonding orbitals are performed using density of states (DOS) spectrum. From photoconductivity measurement, the dark current is seen to be less than photocurrent. The etching analysis was done on (0 0 1) plane of IMLT crystal and rectangular etch pits are observed. Graphical abstract Image 1 Highlights • H⋯H interaction has highest portion in the total area of Hirshfeld surface. • ICT interactions leads to n2(O15) → π*(C13 O14) with stabilization energy of 61.22 kcal/mol. • The first order hyperpolarizability of the IMLT molecule is three times higher than that of urea. • IMLT crystal reveals less etch pit density. [ABSTRACT FROM AUTHOR]

Abstract A single crystal of p-toluidine p-toluenesulfonate (PTPT) has been grown by slow evaporation solution technique (SEST) at room temperature. Single crystal X-ray analysis confirms that grown crystal belongs to the monoclinic structure with space group P2 1. Intermolecular interactions and fingerprint plots of PTPT molecules are executed by Hirshfeld surface analysis. It was found that H···H (44.2%) contacts have maximum intermolecular interactions contributions in the total Hirshfeld surface area. The characteristic absorption band occurs at below 290 nm. The functional groups were identified using FTIR and FT-Raman analyses and compared with theoretical values. The title molecule contains fourteen C H bonds and three O H bonds. The calculated HOMO and LUMO energy values are −6.125 eV and −1.157 eV, respectively. The chemical potential (μ) and electronegativity (χ) values are estimated to be −3.4938 eV and 3.4938 eV, respectively. The strongest negative hyperconjugation occurs due to the charge transfer from the occupied orbital (σ) to the unoccupied orbital (π*) which is calculated for the σ(N20–C21) → π*(N20–O18). The green and red lines in the total density of states (TDOS) spectrum indicate the occupied orbital and virtual orbital levels, respectively. Photoconductivity studies have been done for the grown crystal. It is observed that the dark current is greater than photocurrent. It shows negative photoconductivity nature of PTPT crystal. The etching analysis was executed on (001) plane of PTPT crystal. It has rectangular shape etch pits patterns. Graphical Abstract Unlabelled Image Highlights • The PTPT molecule has 102 fundamental vibration modes. • The first order hyperpolarizability value of PTPT is 4.738 × 10−30 esu. • The grown crystal has negative photoconductivity behaviour. • The etch pit density of PTPT crystal is 5.6 × 103 cm−2. [ABSTRACT FROM AUTHOR]

• 2EIMDT was synthesized and characterized by FTIR, FT-NMR, UV-Vis-NIR and X-ray diffraction. • The presence of amine salt (NH+) and carboxylate (COOˉ) group is confirmed by the molecular structure formation of the title compound. • The stability of 2EIMDT is ensured by hydrogen bonds N–H...O and O–H...O and which is supported by NBO and Hirshfeld surface analysis. The '2-ethylimidazolium d -tartrate (2EIMDT)' C 9 H 14 N 2 O 6 is synthesized and confirmed by experimental NMR, FTIR methods and powder XRD analysis. The HRXRD study reveals that the grown 2EIMDT is an ideally perfect single crystal without having any internal structural grain boundaries. It has good optical transmittance in the wavelength region of 250–1100 nm. The thermal stability of the crystal is ascertained up to 150 °C and the second harmonic generation activity of the crystal was studied by Kurtz-Perry powder technique. Etching analysis reveals the growth pattern and dislocation density of the crystal. A detailed analysis of the intermolecular interactions via Hirshfeld surface analysis and fingerprint plots revealed that the 2EIMDT structure is stabilized mainly by formation of O...H/H...O and H...H hydrogen bonds. The quantum-chemical computations were made to find the molecular properties. The HOMO-LUMO, molecular electrostatic potential, natural bond orbital, nonlinear optical behaviour of the 2EIMDT were studied with the same basis set in the gas phase, theoretically. [Display omitted] [ABSTRACT FROM AUTHOR]