title: Experimental and theoretical investigation of vibrational spectra of coordination polymers based on TCE-TTF.
abstract: The room-temperature infrared and Raman spectra of a series of four isostructural polymeric salts of 2,3,6,7-tetrakis(2-cyanoethylthio)-tetrathiafulvalene (TCE-TTF) with paramagnetic (Co(II), Mn(II)) and diamagnetic (Zn(II), Cd(II)) ions, together with BF(4)(-) or ClO(4)(-) anions are reported. Infrared and Raman-active modes are identified and assigned based on theoretical calculations for neutral and ionized TCE-TTF using density functional theory (DFT) methods. It is confirmed that the TCE-TTF molecules in all the materials investigated are fully ionized and interact in the crystal structure through cyanoethylthio groups. The vibrational modes related to the C=C stretching vibrations of TCE-TTF are analyzed assuming the occurrence of electron-molecular vibration coupling (EMV). The presence of the antisymmetric C=C dimeric mode provides evidence that charge transfer takes place between TCE-TTF molecules belonging to neighboring polymeric networks.
authors.affiliation: Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland. olejniczak@ifmpan.poznan.pl
authors.forename: Iwona
authors.initials: I
authors.lastname: Olejniczak
authors.forename: Andrzej
authors.initials: A
authors.lastname: Lapiński
authors.forename: Roman
authors.initials: R
authors.lastname: Swietlik
authors.forename: Jean
authors.initials: J
authors.lastname: Olivier
authors.forename: Stéphane
authors.initials: S
authors.lastname: Golhen
authors.forename: Lahcène
authors.initials: L
authors.lastname: Ouahab