Analyzing the n®p* electronic transition of formaldehyde in water: a sequential Monte Carlo/time-dependent density functional theory

Journal of the Brazilian Chemical Society

Thaciana Malaspina²  Kaline Coutinho¹  Sylvio Canuto¹ 

[1] ,Universidade de São Paulo Instituto de Química São Paulo SP ,Brazil

关键词: sequential QM/MM;    electronic transition;    solvent effects;    formaldehyde;    TD-DFT;   

DOI  :  10.1590/S0103-50532008000200017

来源: SciELO

【 摘 要 】

The n®p* absorption transition of formaldehyde in water is analyzed using combined and sequential classical Monte Carlo (MC) simulations and quantum mechanics (QM) calculations. MC simulations generate the liquid solute-solvent structures for subsequent QM calculations. Using time-dependent density functional theory in a localized set of gaussian basis functions (TD-DFT/6-311++G(d,p)) calculations are made on statistically relevant configurations to obtain the average solvatochromic shift. All results presented here use the electrostatic embedding of the solvent. The statistically converged average result obtained of 2300 cm-1 is compared to previous theoretical results available. Analysis is made of the effective dipole moment of the hydrogen-bonded shell and how it could be held responsible for the polarization of the solvent molecules in the outer solvation shells.

【 授权许可】

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