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1.
Artigo em Inglês | MEDLINE | ID: mdl-22020167

RESUMO

Chlorocadmiumphosphate Cd(HPO(4))Cl·[H(3)N(CH(2))(6)NH(3)](0.5) crystals containing Cu(II) ions have been successfully synthesized at room temperature by using organic amine 1,6-diamino hexane as a template. The samples are characterized by X-ray powder diffraction, Thermal and spectroscopic studies. These are crystallizes in the monoclinic crystal system with cell dimensions: a=1.7697, b=0.6576, c=1.9026nm and ß=106.5°. FT-IR spectrum showed the absorption bands related to PO(4), NH(3)(+) ions and other organic molecule vibrations originated from the templated molecule. The prepared crystals are stable at room temperature and as well as up to around 300°C which were confirmed by thermal analysis. Optical absorption and EPR studies suggest that Cu(II) ion enters in to the lattice as tetragonally distorted octahedral symmetry, for which crystal field and spin-Hamiltonian parameters are calculated. Bonding parameters are suggesting that there exists partial covalent nature between Cu(II) ions and ligands.


Assuntos
Compostos de Cádmio/química , Cobre/química , Compostos de Cádmio/síntese química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Difração de Pó , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(9): 2115-21, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12788464

RESUMO

The iron phosphate minerals satterlyite and gormanite have been investigated by EPR and optical absorption studies. The optical results indicate the presence of ferrous and ferric ions in both minerals. In gormanite the site symmetry of Fe(III) is near octahedral whereas in satterlyite it is tetragonally distorted. On the other hand, the Fe(II) ions are in tetragonally distorted octahedral site in both minerals. In satterlyite the EPR results indicate the presence of the ferric ion in a tetragonally distorted state together with a small percentage of Mn(II). Crystal field (Dq) and interelectronic parameters (B and C) are evaluated.


Assuntos
Ferro/química , Minerais/química , Fosfatos/química , Análise Espectral
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 57(14): 2781-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11789879

RESUMO

Single crystal electron paramagnetic resonance (EPR) studies on Cu(II) doped zinc potassium phosphate hexahydrate (ZPPH) were carried out at room temperature. The angular variation spectra in the three orthogonal planes indicate that the paramagnetic impurity has entered the lattice substitutionally in place of Zn(II) and the spin Hamiltonian parameters calculated from these spectra are g(xx) = 2.188, g(yy) = 2.032, g(zz) = 2.373, Axx = 50 G, Ayy = 65.0 G and Azz = 80 G. The g and A tensors were coincident and these values matched fairly well with the values obtained from powder spectrum. The bonding parameters have also been calculated.


Assuntos
Cobre/química , Compostos Organometálicos/química , Zinco/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Estrutura Molecular
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 57(14): 2789-94, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11789880

RESUMO

Single crystal electron paramagnetic resonance (EPR) studies were carried at room temperature for VO(II) doped zinc potassium phosphate hexahydrate. The results indicate that the paramagnetic impurity has entered the lattice only substitutionally, as confirmed by the single crystal rotations. The spin Hamiltonian parameters calculated from the spectra are g parallel = 1.9356, g perpendicular = 1.9764, A parallel = 200.9 G and A perpendicular = 76.5 G. The optical absorption spectrum exhibits three bands (800, 670 and 340 nm) suggesting the C4v symmetry and the optical parameters evaluated are Dq = 1492, Ds = -3854 and Dt = 186 cm(-1).


Assuntos
Compostos Organometálicos/química , Vanádio/química , Zinco/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Íons , Óptica e Fotônica
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