title: Analytical First and Second Derivatives for a Fully Polarizable QM/Classical Hamiltonian.
abstract: In this work, we present the derivation and implementation of analytical first and second derivatives for a fully polarizable QM/MM/PCM energy functional. First derivatives with respect to both QM- and MM-described nuclear coordinates and electric perturbations are derived and implemented, and some preliminary application is shown. Analytical second derivatives with respect to nuclear and electric perturbations are then derived, and some numerical test is presented both for a solvated system and for a cromophore embedded in a biological matrix.
authors.affiliation: Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Lipparini
authors.affiliation: Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.|Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Cappelli
authors.affiliation: Gaussian, Inc., 340 Quinnipiac Street Building 40, Wallingford, Connecticut 06492, United States.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Scalmani
authors.affiliation: Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: De Mitri
authors.affiliation: Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Barone