Linear Response Theory and Electronic Transition Energies for a Fully Polarizable QM/Classical Hamiltonian

J Chem Theory Comput. 2012 Nov 13;8(11):4153-65. doi: 10.1021/ct3005062. Epub 2012 Oct 4.

Abstract

A fully polarizable quantum/classical Hamiltonian including SCF (HF or DFT), fluctuating charge, and polarizable continuum regions is introduced and implemented for electronic energies of ground and excited states, using, in the latter case, a linear response formulation. After calibration and validation of the approach, preliminary results are presented for pyrimidine in aqueous solution and for retinal in a rhodopsin mimic. The results are consistent with more tested methodologies and pave the route toward fully consistent yet effective simulations of large systems of technological and/or biological interest in their natural environments.