We illustrate the effect of solvation on the nature of electronic excitations of organic molecules which possess excited states of charge-transfer character. The analysis is carried out using both a continuum model and a polarizable QM/MM method that treats the solvent atomistically and embeds each atom in the solvent with a fluctuating charge which responds to the solute quantum-mechanical electrostatic potential in a self-consistent manner. We also show how solvation dynamics can influence the nature of the excited state of molecular systems. The application of the model to aqueous solutions of doxorubicin and a substituted polythiophene derivative shows that the solvent significantly affects the nature the excited states, which results in an enhanced or reduced charge-transfer character as measured using two of the most popular indices for evaluating the distance traveled by the electrons upon excitation.
On the nature of charge-transfer excitations for molecules in aqueous solution: a polarizable QM/MM study / Egidi F.; Lo Gerfo G.; Macchiagodena M.; Cappelli C.. - In: THEORETICAL CHEMISTRY ACCOUNTS. - ISSN 1432-881X. - ELETTRONICO. - 137:(2018), pp. 82.0-82.0. [10.1007/s00214-018-2259-3]
On the nature of charge-transfer excitations for molecules in aqueous solution: a polarizable QM/MM study
Macchiagodena M.;
2018
Abstract
We illustrate the effect of solvation on the nature of electronic excitations of organic molecules which possess excited states of charge-transfer character. The analysis is carried out using both a continuum model and a polarizable QM/MM method that treats the solvent atomistically and embeds each atom in the solvent with a fluctuating charge which responds to the solute quantum-mechanical electrostatic potential in a self-consistent manner. We also show how solvation dynamics can influence the nature of the excited state of molecular systems. The application of the model to aqueous solutions of doxorubicin and a substituted polythiophene derivative shows that the solvent significantly affects the nature the excited states, which results in an enhanced or reduced charge-transfer character as measured using two of the most popular indices for evaluating the distance traveled by the electrons upon excitation.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.