Solvent Effects on Electronic Spectra

Examine and describe both the highest-occupied and lowest-occupied molecular orbitals (HOMO and LUMO, respectively) oiground state acetone. On which atom(s) is the HOMO primarily concentrated Is it in the o system or in the 7t system Repeat your analysis for the LUMO. 

Compare the dipole moment and the electrostatic potential map for the ground state of acetone to those of the n to pistar state of acetone. Which molecule is more polar Rationalize the differences by appealing to the shape of the orbitals (in ground-state acetone) whose electron populations are changed by excitation. 

Acetone is a moderately polar molecule that can hydrogen-bond with water. Which electronic state of acetone would be stabilized more by moving the molecule from hexane to water Will this shift the n Tt transition to longer or shorter UV wavelengths Explain. 

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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... 

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

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. 

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]. 

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

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. 

Bernal Uruchurtu MI, Ruiz-L6pez MF (2007) Eigen and Zundel ions in aqueous environments. A theoretical study using semi-empirical force fields. In Hemandez-Lamoneda R (ed) Beyond standard quantum chemistry applications from gas to condensded phases. Transworld Research Network, Kerala, pp 65-85 Serrano-Andres L, Fulscher MP, Karlstrom G (1997) Solvent effects on electronic spectra studied by multiconfigurational perturbation theory. Int J Quantum Chem 65(2) 167-181... 

Solvent effects on electronic spectra at liquid interfaces. A continuum electrostatic model. J. Phys. Chem. A 102,9500. 

I. Benjamin, /. Phys. Chem. A, 102, 9500 (1998). Solvent Effects on Electronic Spectra at Liquid Interfaces. A Continuum Electrostatic Model. 

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