%0 Journal Article
%T Theory of Photoinduced Phase Transitions in Molecular Conductors: Interplay Between Correlated Electrons, Lattice Phonons and Molecular Vibrations
%A Kenji Yonemitsu
%J Crystals
%D 2012
%I MDPI AG
%R 10.3390/cryst2010056
%X Dynamics of photoinduced phase transitions in molecular conductors are reviewed from the perspective of interplay between correlated electrons and phonons. (1) The charge-transfer complex TTF-CA shows a transition from a neutral paraelectric phase to an ionic ferroelectric phase. Lattice phonons promote this photoinduced transition by preparing short-range lattice dimerization as a precursor. Molecular vibrations stabilize the neutral phase so that the ionic phase, when realized, possesses a large ionicity and the Mott character; (2) The organic salts ¦È-(BEDT-TTF) 2RbZn(SCN) 4 and ¦Á-(BEDT-TTF)2I3 show transitions from a charge-ordered insulator to a metal. Lattice phonons make this photoinduced transition hard for the former salt only. Molecular vibrations interfere with intermolecular transfers of correlated electrons at an early stage; (3) The organic salt ¦Ê-(d-BEDT-TTF) 2Cu[N(CN) 2]Br shows a transition from a Mott insulator to a metal. Lattice phonons modulating intradimer transfer integrals enable photoexcitation-energy-dependent transition pathways through weakening of effective interaction and through introduction of carriers.
%K photoinduced phase transition
%K neutral-ionic transition
%K charge-order melting
%K metal-insulator transition
%U http://www.mdpi.com/2073-4352/2/1/56