Zakaria Elaoud

Crystal structure of N-benzylmethylammonium dihydrogen-monophosphate monohydrate, [C6H5CH2NH2CH3]H2PO4.H2O

The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, β = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.

Structural, vibrational and thermal studies of a new nonlinear optical crystal tetrapropylammonium dihydrogenmonoarsenate bis arsenic acid

Single crystals of tetrapropylammonium dihydrogenmonoarsenate bis arsenic acid [CH3CH2CH2]4N (H2AsO4) (H3AsO4)2, a potential new nonlinear optical (NLO) material of interest were prepared by the slow evaporation technique and characterized by means of single-crystal X-ray diffraction, thermal analysis, FT-IR and Raman spectroscopy. The title compound belongs to the monoclinic space group Ia with the following unit cell dimensions: a=8.116(2) Ǻ, b=33.673(4) Ǻ, c=8.689(2) Ǻ, β=95.34(2)°. The structure consists of infinite parallel two-dimensional planes built of mutually [H2AsO4(-)] and [H3AsO4] tetrahedra connected by strong O-H⋯O hydrogen bonding giving birth to trimmers. The planes of inorganic groups are alternated with those of the organic cations. The geometry, first hyperpolarizability and harmonic vibrational wavenumbers were calculated by means of density functional theory DFT with the B3LYP/6-31G(d) level of theory. Good consistency was found between the calculated results and the experimental structure, IR, and Raman spectra. The detailed interpretation of the vibrational modes was carried out building on the proposed DFT calculations as primary source of assignment and by comparison with the spectroscopic studies of similar compounds. The first hyperpolarizability βtot of the title compound is about 14.6 times more than that of the reference crystal KDP, which may explain the importance of the compound under study.

Structural, vibrational and DSC investigations of the bis-4-benzyl piperidinium tetraoxoselenate monohydrate crystal.

A new organic-inorganic salt, bis-4-benzyl piperidinium tetraoxoselenate monohydrate has been synthesized and characterized by X-ray diffraction, FT-IR and FT-Raman spectroscopies. The title compound crystallizes in the monoclinic system P2(1)/c at room temperature with the following parameters: a=8.617(3)Å, b=27.140(9)Å, c=10.926(5)Å, β=96.46(4)° and Z=4. Its vibrational spectra have been discussed on the basis on quantum chemical density theory (DFT) calculation using B3LYP/6-31G(*) approach. The role of the intermolecular interaction in this crystal is analyzed. Acidic protons of the selenate group were transferred to the organic cation giving the singly-protonated cation. The ability of ions to form spontaneous three-dimensional structure through O-H···O and N-H···O hydrogen bond is fully utilized. These hydrogen bonds give notable vibrational effects.

Crystal structure of triethylentetraammonium bis monohydrogenmonophosphate dihydrate, [NH3(CH2)2NH2(CH2)2NH2(CH2)2NH3](HPO4)2 · 2H2O

AbstractThe salt triethylentetraammonium bis monohydrogenmonophosphate dihydrate is monoclinic with the following unit cell dimensions: a = 8.462(1), b = 10.500(1), c = 9.520 Å, β = 99.297(1)°, space group P21/n with Z = 2. The structure was solved by the Patterson method and refined to final R value of 0.043 for 1590 independent reflections. The structure consists of infinite parallel two-dimensional [

4-Benzyl-pyridinium hydrogen selenate.

\bar 1

Vibrational spectroscopy, electrical characterization, nonlinear optical properties and DFT calculation of (NEt4)(H2AsO4)(H3AsO4)2

01] planes built of mutually connected ions and water molecules by strong O—H· · ·O and N—H· · ·O hydrogen bonding.

Crystal and Magnetic Structures and Magnetic Properties of Selenate Containing Natrochalcite, AIMII2(H3O2)(SeO4)2 Where A = Na or K and M = Mn, Co, or Ni

Single crystals of a new organic-inorganic crystal, 4-benzylpiperidinium trioxonitrate (4-BPPN) were grown by slow evaporation at room temperature and were characterized by X-ray diffraction, DTA-TG measurement, FT-IR and FT-Raman spectroscopies. The title compound crystallizes in the monoclinic system P21/c at room temperature with the following parameters: a=12.787(8)Å, b=9.007(5)Å, c=11.120(5)Å, β=95.974(2)° and Z=4. Its crystal structure is packing of alternated inorganic and organic layers parallel to (a, c) planes. The different components are connected by a bi-dimensional network of N-H⋯O hydrogen bonds. The ability of ions to form spontaneous three-dimensional structure through N-H⋯O hydrogen bond is fully utilized. These hydrogen bonds give notable vibrational effects. The optimized molecular structure and the vibrational spectra were calculated by the Density Functional Theory (DFT) method using the B3LYP function with the 6-31G(d) basis set. All observed vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our DFT calculations as a primary source of attribution and also by comparison with the previous results for similar compounds. Good consistency is found between the calculated results and the experimental structure, IR, and Raman spectra.

Crystal Structure and Phase Transitions in N-benzyl Piperidinium Dihydrogenmonophosphate, C6H5CH2CHCH2CH2NH2CH2CH2·H2PO4

The structure of the title salt, C12H12N+·HSeO4 −, consists of infinite parallel two-dimensional planes built of 4-benzylpyridinium and hydrogen selenate ions that are mutually connected by strong O—H⋯O and N—H⋯O hydrogen bonds. There are no contacts other than normal van der Waals interactions between the layers.