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Electronic structures of some copper(II)-imidazole complexes
Title
Electronic structures of some copper(II)-imidazole complexes.
Creator
Williams, Chamindra S., Florida Atlantic University, Perumareddi, Jayarama R.
Abstract/Description
Electronic-structure studies of Tetrakis(imidazole)sulphatocopper(II) - Cu(C3H4N2)4SO4 and Tetrakis(imidazole)diperchloratocopper(II) - Cu(C3H4N 2)4(ClO4)2 have been carried out by analysis of electronic spectra, magnetic properties and ESR spectra. Solution spectra of both systems in the visible and UV range as well as unpolarised single-crystal spectrum of Cu(Im)4SO4 in the visible have been recorded. Both ligand-field (LF) and charge-transfer (L --> M) bands have been identified and...
Show moreElectronic-structure studies of Tetrakis(imidazole)sulphatocopper(II) - Cu(C3H4N2)4SO4 and Tetrakis(imidazole)diperchloratocopper(II) - Cu(C3H4N 2)4(ClO4)2 have been carried out by analysis of electronic spectra, magnetic properties and ESR spectra. Solution spectra of both systems in the visible and UV range as well as unpolarised single-crystal spectrum of Cu(Im)4SO4 in the visible have been recorded. Both ligand-field (LF) and charge-transfer (L --> M) bands have been identified and assigned, with the exception of the lowest energy LF band. The Angular Overlap Model has been used to calculate the LF band-maxima and compare with the observed band-maxima The ground-state energy-term for both Cu(Im)4SO4 and Cu(Im)4(ClO4)2 has been established with the use of ESR data to be 2B1g. Magnetic moment for the complexes have been obtained from precise magnetic susceptibility measurements with temperature variation and satisfactorily compared with the calculated values.
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Date Issued
2000
PURL
http://purl.flvc.org/fcla/dt/15775
Subject Headings
Copper compounds, Ligand field theory
Format
Document (PDF)
d(3,7) non-cubic ligand field spectrum and the electronic spectra of quadrate chromium (III) complexes
Title
The d(3,7) non-cubic ligand field spectrum and the electronic spectra of quadrate chromium (III) complexes.
Creator
Williams, Chamindra S., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description
In the first-part of this two-part study, the quadrate energy levels of the d3 configuration including spin-orbit interaction are derived in the rare-earth coupling scheme using ligand-field symmetry parameters Dq, Ds, and Dt, by the method of tensor-operators. Comparison is made to the strong field coupling scheme. In the second part of this study, interpretation of polarised single-crystal spectra of trans-[Cr(tmd)2F2]ClO4, trans-[Cr(en)2(dma)2](ClO4) 3, trans-[Cr(en)2(dmf)Br](ClO4) 2 and...
Show moreIn the first-part of this two-part study, the quadrate energy levels of the d3 configuration including spin-orbit interaction are derived in the rare-earth coupling scheme using ligand-field symmetry parameters Dq, Ds, and Dt, by the method of tensor-operators. Comparison is made to the strong field coupling scheme. In the second part of this study, interpretation of polarised single-crystal spectra of trans-[Cr(tmd)2F2]ClO4, trans-[Cr(en)2(dma)2](ClO4) 3, trans-[Cr(en)2(dmf)Br](ClO4) 2 and trans-[Cr(en)2(dmf)Cl](ClO4) 2 as well as unpolarised single-crystal spectrum of trans-[Cr(en) 2(dmf)2](ClO4)3 and solution spectra of trans-[Cr(pn)(en)F2]ClO4, trans-[Cr(en)2FCl]ClO4 and trans-[Cr(en) 2FBr]ClO4 is made using Gaussian analysis of the bands in both polarisations where possible. Ligand field parameters Dq, Ds, Dt and B are extracted from the spectra using energy matrices in the strong-field coupling scheme by fitting the quadrate components of the two lowest energy cubic quartet bands exactly. Discussion of these parameters and the translated AOM (angular overlap model) parameters, is presented. A thorough interpretation of the high-energy intraconfigurational doublet bands in a number of trans-diacidobis (ethylenediamine) chromium (111) complexes is made using quadrate energy matrices including spin-orbit interaction. Entire programming code for the energy matrices in the rare-earth coupling scheme is included, as are procedures for computing 3-j and 6-j symbols. The complete quadrate energy matrices for d3 configuration in the strong-field coupling scheme with spin-orbit perturbation as well quadrate energy matrices for d3 configuration in the rare-earth coupling scheme are included.
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Date Issued
2005
PURL
http://purl.flvc.org/fcla/dt/12180
Subject Headings
Chemistry, Inorganic, Chemistry, Physical
Format
Document (PDF)