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1.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 72(Pt 5): 709-715, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27698311

RESUMO

Heterocyclic building blocks possessing ethylene spacer and amine functionality such as 1-(2-aminoethyl)piperidine (1,2-AEPi), 2-(2-aminoethyl)pyridine (2,2-AEPy) and 1-(2-aminoethyl)pyrrolidine (1,2-AEPr) were reacted with tetracyanoquinodimethane (TCNQ) to give disubstituted compounds namely bis-(1-(2-aminoethyl)piperidino)dicyanoquinodimethane (1), bis-(2-(2-aminoethyl)pyridino)dicyanoquinodimethane (2) and bis-(1-(2-aminoethyl)pyrrolidino)dicyanoquinodimethane (3). Utilization of 1,2-AEPi, 2,2-AEPy and 1,2-AEPr as disubstituents on TCNQ has resulted in interesting crystal structures. Inter- and intramolecular hydrogen-bond mediated and expanded supramolecular structures were observed in the lattices of the crystals. Strong fluorescence was observed in solids and solutions. (2) showed a strong second harmonic generation (SHG) whereas (1) and (3) were found to be SHG inactive. All compounds possess good thermal stabilities.

2.
Dalton Trans ; 45(20): 8500-5, 2016 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-27116226

RESUMO

The synthesis, crystal structure and physical properties of new disodium trans-diaquabis(oxalato)cobaltate(ii)hexahydrate {Na2[Co(C2O4)2(H2O)2]·6H2O} crystals have been investigated. Single crystal X-ray analysis reveals that this compound crystallizes in the triclinic system with the space group P1[combining macron]. The structure of this complex consists of [Co(C2O4)2(H2O)2](2-) anionic units with a slightly distorted octahedral geometry of cobalt surrounded by four oxygen atoms of two oxalate groups. The anionic units are interlinked by two Na(+) ions with different octahedral and distorted octahedral environments. The electronic absorption spectra of the compound exhibit bands at 208, 246 and 526 nm in the UV and visible regions. A strong blue luminescence was observed at room temperature when excited at 355 nm. The M(H) curve at 2 K shows a significant nonlinear behaviour with almost zero coercivity which clearly indicates an extremely weak antiferromagnetic/ferromagnetic state of the complex.

3.
Artigo em Inglês | MEDLINE | ID: mdl-21636316

RESUMO

Single crystals of γ-glycine, an organic nonlinear optical material have been synthesized in the presence of potassium fluoride (KF) by slow evaporation technique at ambient temperature. The size of the grown crystal is up to the dimension of 12 mm×10 mm×8 mm. The γ-phase was confirmed by single crystal X-ray diffraction, powder XRD and the FTIR analysis. Optical absorption spectrum reveals that the grown crystal has good optical transparency in the entire visible region with an energy band gap of 5.09 eV, which is an essential requirement for a nonlinear optical crystal. Thermal stability of the grown γ-glycine crystal was determined using the thermo gravimetric and differential thermal analyses. The NLO activity of γ-glycine was confirmed by the Kurtz powder technique using Nd:YAG laser and the grown crystal exhibits high relative conversion efficiency when compared to potassium dihydrogen phosphate (KDP).


Assuntos
Fluoretos/química , Glicina/química , Óptica e Fotônica , Fótons , Compostos de Potássio/química , Cristalização , Cristalografia por Raios X , Análise Diferencial Térmica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): o1734, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-21587951

RESUMO

In the title 2H-pyrazolo-[4,3-c]pyridine derivative, C(32)H(27)Cl(2)N(3), the dihydro-pyrazole ring adopts an envelope conformation and the piperidine fused ring a twisted-chair conformation. Two short intra-molecular C-H⋯Cl contacts are observed. The crystal packing is characterized by dimeric C-Cl⋯π inter-actions involving the 5-benzyl ring, with Cl⋯centroid and closest atomic Cl⋯π distances of 3.778 (2) and 3.366 (4) Å, respectively.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): o1753, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-21587969

RESUMO

In the title compound, C(27)H(21)NO(2), the half-chair conformation of the alicyclic rings gives rise to a slightly folded structure of the central tricyclic tetra-hydrophenanthridine unit. Tandem intra-molecular O-H⋯N and O-H⋯O hydrogen bonds give rise to adjacent S(6) and S(5) rings, respectively, which dictate the conformation of the 5-aryl substituent. In the crystal structure, an inter-molecular C-H⋯O contact generates chains parallel to [101]. Short O-H⋯π and C-H⋯π contacts are also observed.

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