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Abstract A novel hybrid material, [C 10 H 22 N 2 ] 3 ·PbCl 5 ·3Cl·3H 2 O, has been synthesized and its structure was determined by single-crystal X-ray diffraction. In the atomic arrangement, the different entities are held together through N H⋯Cl, O H⋯Cl and O H⋯O hydrogen bonds to form a three-dimensional network. Intermolecular interactions were investigated by Hirshfeld surfaces. The powder XRD data confirms the phase purity of the crystalline sample. The resulting IR spectrum calculated by the DFT/B3LYP/LanL2DZ method, is similar to the experimental spectrum allowing a good correlation between the experimental and theoretical wavenumbers. The optical properties in the UV–visible region have been explored by the UV–visible absorption. The photoluminescence (PL) spectroscopy, which was investigated at room temperature, exhibited one emission at 426 nm. Thermal analysis discloses a phase transition at 435 K and the decomposition of the sample starts from 554 K. Graphical abstract Image 1 Highlights • The entities [C 10 H 22 N 2 ]2+ and [PbCl 5 ]3- ions are interconnected by means of hydrogen bonding contacts, forming a three-dimensional network. • The vibrational frequencies were also predicted from the calculated intensities by DFT method. • The optical properties were studied by UV–visible absorption and photoluminescence study. • This compound was characterized by thermal analysis between 300 and 750 K. [ABSTRACT FROM AUTHOR]

Abstract In this study, a new organic-inorganic hybrid metal compound (C 5 H 14 N 2) 2 [SnCl 6 ] 2 ·5H 2 O was crystallized at room temperature in the orthorhombic system (space group P2 1 2 1 2 1) where the structure is determined by single crystal X-ray diffraction analysis. The examination of the structure shows the cohesion and stability of the atomic arrangement result from the establishment of N—H⋯Cl, O(W)—H(W)⋯Cl, N—H⋯O(W) and O(W)—H(W)⋯O(W) hydrogen bonds between 1-methylpiperazine-1,4-diium (C 5 H 14 N 2)2+cations, isolated (SnCl 6)2– anions and water molecules to form organic and inorganic layers parallel to the (a, c) plane and alternate along the b-axis. Hirshfeld surface analysis was used to investigate intermolecular interactions, as well 2D fingerprint plots were conducted to reveal the contribution of these interactions in the crystal structure quantitatively. The solid phase FTIR and FT-Raman spectra of this compound have been recorded in the regions 400–4000 and 100–500 cm−1, respectively. The vibrational frequencies were also predicted from the calculated intensities by DFT method and were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. Besides, the optical proprieties were investigated by UV-visible and photoluminescence spectroscopy studies in the region 200–700 nm and the electronic properties HOMO and LUMO energies were measured by TD-DFT approach. Moreover, this compound was characterized by thermal analysis between 300 and 500 K which revealing two phase transitions. Finally, X-ray photoelectron spectroscopy (XPS) analysis is reported to determine the degree of oxidation of tin in this compound and analyzing the surface chemistry of (C 5 H 14 N 2) 2 [SnCl 6 ] 2 ·5H 2 O. Graphical abstract Image 1 The different characterization techniques of (C 5 H 14 N 2) 2 [SnCl 6 ] 2 ·5H 2 O. Highlights • The crystal structure exhibits organic and inorganic layers parallel to the (a, c) plane and alternate along the b-axis. • The 3D Hirshfield surfaces and the associated 2D fingerprint plots were investigated for intermolecular interactions. • The vibrational frequencies were also predicted from the calculated intensities by DFT method and were compared with the experimental frequencies. • The optical properties were studied by UV–visible absorption, photoluminescence spectroscopy studies and XPS technique. • This compound was characterized by thermal analysis between 300 and 500. [ABSTRACT FROM AUTHOR]

The synthesis and the structure of (C 10 H 15 N 2 ) 4 (Li) 2 (P 6 O 18 )(H 2 O) 6 are described. This compound crystallizes in the triclinic system, with the centric space group P-1 and the following unit cell parameters: a  = 9.7762(6), b  = 10.2502(8), c  = 15.2173(11) Å, α  = 92.588(4), β  = 98.855(4), γ  = 115.724(4)°, Z  = 2 and V  = 1346.62(17) Å 3 . The crystal structure has been solved and refined to R  = 0.0452 and Rw  = 0.1121. [Li 2 (P 6 O 18 )(H 2 O)] 4- entities are associated by strong O H⋯O hydrogen bonds to form inorganic layers lying in the (a, b) plane. These layers are interconnected with the organic entities via N H⋯O and C H⋯O hydrogen bonds. In this atomic arrangement, H bonds between the different species play an important role in the three-dimensional network. The contacts enrichment ratios derived from the Hirshfeld surface analysis show that the crystal packing is stabilized by ionic bridges Li + … O, strong N/O H⋯O hydrogen bonds but also hydrophobic interactions between the two independant 1-phenylpiperazine-1,4-dium ligands. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gaps of the new compound were computed. The title compound was further characterized by FT-IR and NMR spectroscopies. The crystal symmetry was confirmed by 31 P and 7 Li MAS NMR and the vibrational absorption bands were identified by infrared spectroscopy. The new compound was also characterized by thermal analysis to determine the thermal behavior. [ABSTRACT FROM AUTHOR]

(C 6 H 7 FN) 4 (Li) 2 (P 6 O 18 ) (H 2 O) 6 (I) , a new organic cyclohexaphosphate, has been synthesized and grown at room temperature by an acid/base reaction between H 6 P 6 O 18 and 2-fluoroaniline as an organic template. The crystal structure of (I) was solved by single crystal X-ray diffraction analysis and it was found that the material belongs to triclinic system with space group P-1 and refined R -factor of 0.0520. Adjacent P 6 O 18 rings are connected via corner-sharing by LiO 4 tetrahedra, generating anionic [Li 2 P 6 O 18 ·H 2 O] 4- layers parallel to the ( a , b ) plane. The 2-fluoro-anilinium cations are inserted in the interlayer space and interact with the inorganic framework through N H⋯O and O H⋯O hydrogen-bonding interactions. Additional stabilization is provided by strong N H⋯F and weak C H⋯O hydrogen bonds. Hirshfeld surface analysis reveals the nature of intermolecular contacts of the title compound and their enrichment ratio reveals if they are over-represented. The crystal packing is a combination of strong electrostatic attractive interactions and of weaker hydrophobic contacts. The title compound was further characterized by FT-IR and NMR spectroscopies. Crystal symmetry is confirmed by 31 P magic angle spinning NMR and the vibrational absorption bands were identified by infrared spectroscopy. Electrical conductivity was studied using impedance spectroscopy and results showed that the conductivity at 150 °C was equal to 4.93 × 10 −4  S cm −1 . It is therefore concluded that (C 6 H 7 FN) 4 (Li) 2 (P 6 O 18 ) (H 2 O) 6 can be further used in lithium batteries. [ABSTRACT FROM AUTHOR]

Two new organic-inorganic hybrid materials, 4-methoxybenzylammonium nitrate, (C 8 H 12 NO)·[NO 3 ] (I) , and 2-(1-piperazinyl)pyrimidinium bis(perchlorate), (C 8 H 14 N 4 )·[ClO 4 ] 2 (II) , have been synthesized by an acid/base reaction at room temperature, their structures were determined by single crystal X-ray diffraction. Compound (I) crystallizes in the orthorhombic system and Pnma space group with a  = 15.7908 (7), b  = 6.8032 (3), c  = 8.7091 (4) Å, V  = 935.60 (7) Å 3 with Z  = 4. Full-matrix least-squares refinement converged at R  = 0.038 and w R ( F 2 ) = 0.115. Compound (II) belongs to the monoclinic system, space group P 2 1 / c with the following parameters: a  = 10.798(2), b  = 7.330(1), c  = 21.186(2) Å, β  = 120.641 (4)°, V  = 1442.7 (3) Å 3 and Z  = 4. The structure was refined to R  = 0.044, w R ( F 2 ) = 0.132. In the structures of ( I ) and ( II ), the anionic and cationic entities are interconnected by hydrogen bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms in (II) were compared. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gaps of both compounds were computed. The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state 13 C, 35 Cl and 15 N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands. [ABSTRACT FROM AUTHOR]

The reaction of perchloric acid with 1-(2-aminoethyl)piperazine or 5,6-dimethyl-benzimidazole results in the formation of 1-(2-amonioethyl)piperazine-1,4-dium triperchlorate hydrate (C 6 H 18 N 3 )·(ClO 4 ) 3 ·H 2 O (I) or 5,6-dimethyl-benzylimidazolium perchlorate (C 9 H 11 N 2 )·ClO 4 (II) . Both compounds were fully structurally characterized including single crystal X-ray diffraction analysis. Compound (I) crystallizes in the centrosymmetric triclinic space group P 1 ¯ with the lattice parameters a = 7.455 (2), b = 10.462 (2), c = 10.824 (2) Å, α = 80.832 (2), β = 88.243 (2), γ = 88.160 (2) °, Z = 2 and V = 832.77 (3) Å 3 . Compound (II) has been found to belong to the P 2 1 /c space group of the monoclinic system, with a  = 7.590 (3), b  = 9.266 (3), c  = 16.503 (6) Å, β = 107.38 (2) °, V = 1107.69 (7) Å 3 and Z = 4. The structures of (I) and (II) consist of slightly distorted [ClO 4 ] - tetrahedra anions and 1-(2-amonioethyl)piperazine-1,4-dium trication (I) or 5,6-dimethyl-benzylimidazolium cations (II) and additionally a lattice water in (I) . The crystal structures of ( I) and ( II) exhibit complex three-dimensional networks of H-bonds connecting all their components. In the atomic arrangement of (I) , the ClO 4 − anions form corrugated chains, while in (II) the atomic arrangement exhibits wide pseudo-hexagonal channels of ClO 4 tetrahedra including the organic entities. The lattice water serves as a link between pairs of cations and pairs of anions via several O H⋯O and N-H⋯O interactions in compound (I) . The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state 13 C, 35 Cl and 15 N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived. [ABSTRACT FROM AUTHOR]

A novel hybrid material, C 6 H 16 N 2 OPbCl 4 , has been successfully synthesized in nitrogen atmosphere by slow evaporation at room temperature. The compound structure was determined by single-crystal X–ray diffraction and crystallizes in the triclinic space group P -1 ( a   =  5.9926(2) Å, b   =  10.3691(5) Å, c   =  11.3558(4) Å, α = 111.755(4)°, β =  96.080(3)°, γ  = 105.948(4)°, Z  = 2) at 293 K. The structure is built up from anionic 1-D polymeric chains of PbCl 4 O octahedral extended along the ( b + c )-axis. These chains are interconnected by O H⋯Cl hydrogen bonds to form inorganic layers parallel to ( a, b + c ) plane. The organic layers are inserted between the inorganic ones and connect them through N H⋯Cl and C H⋯Cl hydrogen bonds to build a three dimensional network. To gain more information about intermolecular interaction we used Hirshfeld surfaces associated with 2D finger plots. The optical and PL properties of the compound were investigated in the solid state at room temperature and exhibited two bands at 250 and 290 nm and a photoluminescence emission at 529 nm. Raman and infrared spectra were used to gain more information for vibrational modes of the title compound. As for thermal analysis, DSC analysis shows that this compound is stable at temperature below melting point. Finally, XPS analysis is achieved for analyzing the surface chemistry of C 6 H 16 N 2 OPbCl 4 crystals. [ABSTRACT FROM AUTHOR]

A novel hybrid compound, bis(4-methylanilinium)hexachlorostannate(IV) monohydrate, formulated as (C 7 H 10 N) 2 [SnCl 6 ]·H 2 O, has been prepared and characterized by powder and single crystal X-ray diffraction (XRD), Hirshfeld surface analysis, infrared spectroscopy (IR), optical study, differential thermal analysis(DTA) and X-ray photoelectron spectroscopy analysis (XPS). The title compound crystallizes in the monoclinic space group P 2 1 / c with a = 13.093(1)Å, b = 7.093(6)Å, c = 24.152(2)Å, β = 98.536(4)⁰ and V = 2218.4(4) Å 3 . Their crystal structure exhibits alternating inorganic layers parallel to the ( ab ) plane at z = n/2. The different entities, [SnCl 6 ] 2- , organic cations and water molecules, are connected via hydrogen bonds to form a three-dimensional network. The powder XRD data confirms the phase purity of the crystalline sample. The intermolecular interactions were investigated by Hirshfeld surfaces. The vibrational absorption bands were identified by IR spectroscopy and have been discussed. The optical properties of the crystal were studied by using optical absorption, UV–visible absorption and photoluminescence spectroscopy studies. The compound was also characterized by DTA to determine its thermal behavior with respect to the temperature. Finally, XPS technique is reported for analyzing the surface chemistry of this compound. [ABSTRACT FROM AUTHOR]

The synthesis and the X-ray structure of the Zn(II) zwitterionic complex:1-ethylpiperaziniumtrichlorozincate (II) are described. In the atomic arrangement, the ZnCl 3 N entities, grouped in pairs, are deployed along the b -axis to form layers. The organic entities are inserted between these layers through N H⋯Cl and C H⋯Cl hydrogen bonds to form infinite three-dimensional network. The 3D Hirshfeld surfaces were investigated for intermolecular interactions. The optimized geometry, Mulliken charge distribution, molecular electrostatic potential (MEP) maps and thermodynamic properties have been calculated using the Lee-Yang-Parr correlation functional B3LYP with the LanL2DZ basis set. The HOMO and LUMO energy gap and chemical reactivity parameters were made. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray crystal structure. The vibrational absorption bands were identified by infrared spectroscopy. DFT calculations allowed the attribution of the NMR peaks and of the IR bands. [ABSTRACT FROM AUTHOR]

The crystal structure of the new complex [Co(C 5 H 7 N 3 O) 2 (H 2 O) 4 ](NO 3 ) 2 ⋅4H 2 O synthesized in aqueous solution has been determined by single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P 1 ¯ with lattice parameters: a = 7.3056(2), b = 8.4065(2), c = 10.4724(3) Å, α = 103.9470(19), β = 105.6600(14), γ = 91.1350(18)°, V = 598.54(3) Å 3 and Z = 1. The Co(II) central ion is in a slightly distorted octahedral coordination geometry formed by two nitrogen atoms of two 2-amino-6-methoxypyrimidine ligands and four oxygen atoms of coordinated water molecules. The crystal packing is stabilized by intermolecular O H⋯O, N H⋯O and C H⋯O hydrogen bonds which link the molecules into a three-dimensional network. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived. The vibrational absorption bands were identified by infrared spectroscopy. The compound was characterized by thermal analysis to determine its thermal behavior with respect to temperature. [ABSTRACT FROM AUTHOR]

A new Bi(III) halide complex, [C 6 H 16 N 2 ] 5 Bi 2 Br 10 (BiBr 6 ) 2 ·2H 2 O has been synthesized at room temperature in the presence of 1,4-dimethylpiperazine by slow evaporation technique and characterized by physicochemical methods. It crystallizes in a triclinic centrosymmetric space group, P -1. The crystal lattice is composed of two types of anionic entities [Bi 2 Br 10 ] 4− and [BiBr 6 ] 3− surrounded by 1,4-dimethylpiperazine-1,4-diium cations and water molecules. The anionic part was found for the first time in halobismuthate(III) solid complexes. In the crystal, the components are linked by C-H…Br(Ow) and Ow-H…Br hydrogen bonds to built three-dimensional network. The vibrational absorption bands were identified by Infrared and Raman spectroscopy. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray structure. Intermolecular hydrogen bonding was investigated by means of the Hirshfeld surfaces. The percentages of hydrogen bonding interactions are analyzed by Fingerprint plots of Hirshfeld surface. The optical properties of this compound were studied by UV–Vis and luminescence spectroscopy. The DSC curve shows that this compound is stable below melting point. [ABSTRACT FROM AUTHOR]

The new organic-inorganic compound [C 6 H 16 N 2 O](SnCl 6 ).H 2 O was synthesized and single crystals were grown from an aqueous solution through these slow evaporation technique. The atomic arrangement can be described by organic-inorganic layers parallel to the (a, c) plane. These layers are connected via hydrogen bonds (O H⋯O and C H⋯Cl) to build a three dimensional arrangement. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray structure. The vibrational absorption bands were identified by infrared spectroscopy and Raman scattering. DFT calculations allowed the attribution of the IR bands. The 3D Hirshfeld surfaces and the associated 2D fingerprint plots were investigated for intermolecular interactions. X-ray photoelectron spectroscopy analysis (XPS) is a technique for analyzing the surface chemistry of a compound. It was employed to measure the elemental composition and electronic state of the elements within a material. The DSC profile shows endothermic peaks centered at approximately 343, 370 and 552 K. [ABSTRACT FROM AUTHOR]

Single crystals of a new organic cyclohexaphosphate (C 8 H 12 N) 4 (Li) 2 (P 6 O 18 )(H 2 O) 6 prepared by an acid/base reaction between cyclohexaphosphoric acid H 6 P 6 O 18 and 2,6-dimethylaniline, have been successfully grown by slow evaporation technique at room temperature. This compound was characterized using X-ray diffraction (XRD) and FT-IR spectroscopy. The results show that the title compound was phased with a triclinic structure and P-1 space group. The crystal structure was solved by using 5203 independent reflections with a final R value of 0.031. The P 6 O 18 ring is centrosymmetrical. Its main geometrical features are those commonly observed in others cyclohexaphosphates. The atomic arrangement of this compound can be described by an organization in a three-dimensional framework, built up from alternated organic and inorganic species. Adjacent P 6 O 18 rings are linked via corner-sharing by LiO 4 tetrahedra, generating anionic [Li 2 (P 6 O 18 )(H 2 O)] 4- layers parallel to (110). Charge balance is achieved by the protonated amine which is trapped in the interlayer space and interacts with the organic framework through strong and medium hydrogen bonding. An extensive network of N H⋯O and O H⋯O hydrogen-bonding interactions link the components into a three-dimensional network and additional stabilization is provided by weak C H⋯O hydrogen bonds. Intermolecular interactions were investigated by Hirshfeld surfaces. The vibrational absorption bands were identified by infrared spectroscopy. The stretching modes of P 6 O 18 ring and band assignments are described. [ABSTRACT FROM AUTHOR]

A new organic–inorganic hybrid material with the formula [C 8 H 12 N] 3 BiCl 6 has been synthesized and characterized by spectroscopic techniques and single crystal X-ray structure determination. This compound crystallizes in the non-centrosymmetric space group Pna 2 1 of the orthorhombic system with crystallographic parameters a = 25.5620(2), b = 16.7170(5), c = 7.8840(4) Å, V = 3369.0(2) Å 3 and Z = 4. Its structure consists of discrete [BiCl 6 ] 3− anions, showing the distorted octahedral geometry, surrounded by three crystallographically independent 2-phenylethylammonium cations. The crystal packing is governed by the formation of a number of N–H⋯Cl hydrogen bonds arranged in a three-dimensional network. Crystal structure analysis supported with the Hirshfeld surface and fingerprint plots enabled the identification of the significant intermolecular interactions. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray structure. The optical properties of [C 8 H 12 N] 3 BiCl 6 were investigated by UV–Vis and luminescence spectroscopy. The differential scanning calorimetry (DSC) revealed that the title compound is stable up to 210 °C. [ABSTRACT FROM AUTHOR]

The synthesis, crystal structure and spectroscopic characterization of a new chlorocadmate template by the 1-(2-hydroxyethyl)piperazine ligand are reported. In the atomic arrangement, the CdCl 5 O entities are deployed in corrugated rows along the a -axis at y = 1/4 and y = 3/4 to form layers parallel to the ( a,b ) plane. In these crystals, piperazinediium cations are in a chair conformation and are inserted between these layers through N H⋯Cl, C H⋯Cl, O H⋯Cl and N H⋯O hydrogen bonds to form infinite three-dimensional network. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that H⋯Cl and C H⋯H C intermolecular interactions are the most abundant contacts of the organic cation in the crystal packing. The crystal contacts enrichments reveals that, the Cd ++ … Cl − salt bridges, the Cd⋯O complexation and O H⋯Cl- and N H⋯Cl-strong H-bonds are the driving forces in the packing formation. The presence of twelve independent chloride anions and four organic cation in the asymmetric unit allowed comparing their contact propensities. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray structure. Additional characterization of this compound has also been performed by IR spectroscopy. [ABSTRACT FROM AUTHOR]

The synthesis, crystal structure and spectroscopic characterization of the novel 1-(2-hydroxyethyl)piperaziniumtrichlorozincate(II) zwitterionic complex are reported. In the atomic arrangement, the ZnCl 3 N entities, grouped in pairs, are deployed in rows along the a -axis to form layers parallel to the ( a , c ) plane. The organic molecules are inserted between these layers through N-H…Cl, C-H…Cl, O-H…Cl and N-H…O hydrogen bonds to form infinite three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces. The 13 C and 15 N CP-MAS NMR spectra are in agreement with the X-ray structure. The vibrational absorption bands were identified by infrared spectroscopy. DFT calculations allowed the attribution of the NMR peaks and of the IR bands. [ABSTRACT FROM AUTHOR]

A novel organic–inorganic hybrid material, C 6 H 15 N 2 CdCl 3 .H 2 O, was synthesized, and its structure was determined at room temperature in the monoclinic space group P2 1 / n with the following parameters: a = 10.3829 (17), b = 7.7459 (12), c = 14.905 (2) Å, β = 98.801 (15), and Z = 4. Its crystal structure is characterized by one-dimensional polymeric chains of edge-sharing CdCl 5 N distorted octahedra. These chains are linked to the water molecules via O H … Cl hydrogen bonds to form layers parallel to the ( b , a + c ) plane. The crystal structure was stabilized by an extensive network of N H … Cl, O H … Cl and N H … O hydrogen bonds. The differential scanning calorimetry (DSC) reveals that the title compound is stable until 101.6 °C. The optimized geometry parameters, normal mode frequencies, and corresponding vibrational assignments of the present compound were theoretically examined by DFT/B3LYP method with the Lanl2dz basis set. The FT-IR spectrum of the polycrystalline sample was examined and compared to the calculated spectrum. The calculated results showed that the optimized geometry could well reproduce the crystal structure and that the theoretical vibrational frequency values were in good agreement with their experimental counterparts. [ABSTRACT FROM AUTHOR]

Synthesis and structures of two new isomeric organic amine perchlorate salts with the general formula (ClC 7 H 6 NH 3)ClO 4 ·H 2 O, 3-Cl-2-(CH 3)C 6 H 3 NH 3 ClO 4· H 2 O (I) and 5-Cl-2-(CH 3)C 6 H 3 NH 3 ClO 4· H 2 O (II) , are reported. They crystallize in the monoclinic system and are isostructural. In the crystal packing of these organic salts, ClO 4 − anions, water molecule and –NH 3 + groups have a layered organization around the z = 1/4 and z = 3/4 planes. The cations are linked to successive layers through hydrogen bonds to establish a three-dimensional network, involving the hydrogen atoms of the NH 3 groups. CP–MAS NMR, IR, UV–Visible spectroscopy and differential scanning calorimetry (DSC) were used to characterize these compounds. Image 1 • Structural study of two isostructural hydrates of isomeric organic amine perchlorates. • NMR signals are in full agreement with the crystallographic data. • DFT calculations allow the attribution of the experimental NMR lines. • Hirshfeld surface analysis was used to evaluate intermolecular contacts. • The electronic properties such as HOMO and LUMO energies were studied. [ABSTRACT FROM AUTHOR]