title: Polarizable embedding with a multiconfiguration short-range density functional theory linear response method.
abstract: We present here the coupling of a polarizable embedding (PE) model to the recently developed multiconfiguration short-range density functional theory method (MC-srDFT), which can treat multiconfigurational systems with a simultaneous account for dynamical and static correlation effects. PE-MC-srDFT is designed to combine efficient treatment of complicated electronic structures with inclusion of effects from the surrounding environment. The environmental effects encompass classical electrostatic interactions as well as polarization of both the quantum region and the environment. Using response theory, molecular properties such as excitation energies and oscillator strengths can be obtained. The PE-MC-srDFT method and the additional terms required for linear response have been implemented in a development version of Dalton. To benchmark the PE-MC-srDFT approach against the literature data, we have investigated the low-lying electronic excitations of acetone and uracil, both immersed in water solution. The PE-MC-srDFT results are consistent and accurate, both in terms of the calculated solvent shift and, unlike regular PE-MCSCF, also with respect to the individual absolute excitation energies. To demonstrate the capabilities of PE-MC-srDFT, we also investigated the retinylidene Schiff base chromophore embedded in the channelrhodopsin protein. While using a much more compact reference wave function in terms of active space, our PE-MC-srDFT approach yields excitation energies comparable in quality to CASSCF/CASPT2 benchmarks.
authors: Laboratorium fur Physikalische Chemie, ETH Zürich, Vladimir Prelog Weg 2, CH-8093 Zürich, Switzerland.
authors: Erik Donovan
authors: ED
authors: Hedegård
authors: Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
authors: Jógvan Magnus Haugaard
authors: JM
authors: Olsen
authors: Laboratorium fur Physikalische Chemie, ETH Zürich, Vladimir Prelog Weg 2, CH-8093 Zürich, Switzerland.
authors: Stefan
authors: S
authors: Knecht
authors: Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
authors: Jacob
authors: J
authors: Kongsted
authors: Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
authors: Hans Jørgen Aagaard
authors: HJ
authors: Jensen
mesh_terms: D000096:Acetone / Q000737:chemistry; D016014:Linear Models; D008958:Models, Molecular; D011789:Quantum Theory; D012176:Retinoids / Q000737:chemistry; D012243:Rhodopsin / Q000737:chemistry; D012984:Software; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D055672:Static Electricity; D014498:Uracil / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D012176:Retinoids; D012996:Solutions; D012997:Solvents; C121835:retinylidene chromophore; D014867:Water; D000096:Acetone; D014498:Uracil; D012243:Rhodopsin