Effect on electronic spectra

Iordanov TD, Davis JL, Masunov AE, Levenson A, Przhonska OV, Kachkovski AD (2009) Symmetry breaking in cationic polymethine dyes, part 1 ground state potential energy surfaces and solvent effects on electronic spectra of streptocyanines. Int J Quantum Chem 109 3592-3601... 

Muino PL, Callis PR (1994) Hybrid simulations of solvation effects on electronic-spectra -indoles in water. J Chem Phys 100(6) 4093 1109... 

M. F. Nicol, Solvent effects on electronic spectra, Appl. Spect. Rev. 8 183 (1974). 

Mulliken also studied other band spectra of diatomic molecules. Only one such study will be mentioned here and that is his study of copper iodide (Mulliken 1925c), where he examined the copper isotope effect. Mulliken s pioneering work was followed by more papers on isotope effects on electronic spectra (visible and UV) which will not be detailed here. Many of these papers deal with diatomics since the theory of such spectra is much better understood than that for general polyatomic systems. Further discussion of isotope effects on spectra will be mainly restricted to their use in the discovery of less abundant isotopes. 

Electronic and vibrational spectroscopy continues to be important in the characterization of iron complexes of all descriptions. Charge-transfer spectra, particularly of solvatochromic ternary diimine-cyanide complexes, can be useful indicators of solvation, while IR and Raman spectra of certain mixed valence complexes have contributed to the investigation of intramolecular electron transfer. Assignments of metal-ligand vibrations in the far IR for the complexes [Fe(8)3] " " were established by means of Fe/ Fe isotopic substitution. " A review of pressure effects on electronic spectra of coordination complexes includes much information about apparatus and methods and about theoretical aspects, though rather little about specific iron complexes. ... 

L. Serrano-Andres, M. P. Fulscher and G. Karlstrom, Solvent effects on electronic spectra studied by multiconfigurational perturbation theory, Int. J. Quantum Chem., 65 (1997) 167-181. 

Py) < (CN , OH ) < (CN, CN ). A molecular orbital treatment advanced for the elucidation of axial ligation effects on electronic spectra of the corrin complexes (19) may be applied in this case. 

A consistent model permitting rationalization and prediction of the solvato-chromic behaviour of coordination compounds with MLCT absorption has been described [428]. According to this qualitative model, the changing relationship between the metal-ligand bond dipolarities in the ground and MLCT excited state determines whether the complex is negatively, positively, or not solvatochromic [428]. For comprehensive reviews on solvent effects on electronic spectra of metal complexes, see references [15, 17]. 

Other semiempirical Hamiltonians have also been used within the BKO model. A Complete Neglect of Differential Overlap (CNDO/2) ° study of the effect of solvation on hydrogen bonds has appeared. o The Intermediate Neglect of Differential Overlap (INDO) °2 formalism has also been employed for this purpose.2011 Finally, the INDO/S model,which is specifically parameterized to reproduce excited state spectroscopic data, has been used within the SCRF model to explain solvation effects on electronic spectra.222,310-312 jhis last approach is a bit less intuitively straightforward, insofar as the INDO/S parameters themselves include solvation by virtue of being fit to many solution ultraviolet/visible spectroscopic data.29J... 

Yto solvent effects on electronic spectra (1 and y are found to have a negligible effect. 

B Uno and T Kubota. New Description of the Substituent Effect on Electronic Spectra by Means of Substituent Constants. Part VII. Electronic Spectra of Substituted Benzenes. J. Molec. Structure (Theochem) 230 247-261, 1991. 

In the following few chapters the electronic spectra of various types of molecules have been discussed. The electronic spectra of molecules are modified b> substitution with different groups. Both electronic and stcrie interactions of groups are important in electronic spectra. The term, electronic interaction, includes both inductive and resonance (mesomeric) interactions, although the influence of the latter may be more prominent. The substituent effects on the spectra of different chromophores and molecules will be discussed appropriately in the following chapters. Ster e effects on electronic spectra have been dealt with separately in Chapter S. 

Abe has developed an alternative semiclassical theory of the solvent effects on electronic spectra. This theory is based on die averaging of the intermolecular interaction energy over all solute-solvent configurations within the approximation of pair interactions. The theory involves the dipole moments and polarizabihties of the solute molecule and takes into account the temperature dependence arising from the Boltzmann factor. 

A. T. Amos and B. L Burrows, Adv. Quantum Chem., 7,289 (1973). Solvent-Shift Effects on Electronic Spectra and Excited-State Dipole Moments and Polarizabilities. 

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