title: Self-consistent continuum solvation for optical absorption of complex molecular systems in solution.
abstract: We introduce a new method to compute the optical absorption spectra of complex molecular systems in solution, based on the Liouville approach to time-dependent density-functional perturbation theory and the revised self-consistent continuum solvation model. The former allows one to obtain the absorption spectrum over a whole wide frequency range, using a recently proposed Lanczos-based technique, or selected excitation energies, using the Casida equation, without having to ever compute any unoccupied molecular orbitals. The latter is conceptually similar to the polarizable continuum model and offers the further advantages of allowing an easy computation of atomic forces via the Hellmann-Feynman theorem and a ready implementation in periodic-boundary conditions. The new method has been implemented using pseudopotentials and plane-wave basis sets, benchmarked against polarizable continuum model calculations on 4-aminophthalimide, alizarin, and cyanin and made available through the Quantum ESPRESSO distribution of open-source codes.
authors.affiliation: SISSA - Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Iurii
authors.initials: I
authors.lastname: Timrov
authors.affiliation: Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, Pisa 56126, Italy.
authors.forename: Oliviero
authors.initials: O
authors.lastname: Andreussi
authors.affiliation: SISSA - Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Biancardi
authors.affiliation: Theory and Simulation of Materials (THEOS), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
authors.forename: Nicola
authors.initials: N
authors.lastname: Marzari
authors.affiliation: SISSA - Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Baroni