%0 Journal Article %T Charge localization in one-dimensional tetramerized organic conductors: the special case of (tTTF)2ClO4 %+ Institute of Molecular Physics %+ Institut des Sciences Chimiques de Rennes (ISCR) %+ Universität Stuttgart [Stuttgart] %A Frąckowiak, Arkadiusz %A Świetlik, Roman %A Jeannin, Olivier %A Fourmigué, Marc %A Li, Weiwu %A Dressel, Martin %Z We thank for support from German Academic Exchange Service (DAAD). We are also indebted to Jean-Paul Pouget for discussion. %< avec comité de lecture %@ 0953-8984 %J Journal of Physics: Condensed Matter %I IOP Publishing %V 31 %N 15 %P 155601 %8 2019-02-18 %D 2019 %R 10.1088/1361-648X/ab00b5 %M 30669131 %K crystal structure %K IR and Raman spectra %K charge localization %K one-dimensional organic conductor %K phase transition %Z Chemical Sciences/Material chemistry %Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles %X We report a detailed structural and spectroscopic study of the 1D 2:1 cation radical salt (tTTF)ClO, where tTTF  =  trimethylenetetrathiafulvalene, which exhibits a semiconductor-semiconductor phase transition at ca. T  =  137 K. Crystal structures are determined above and below the transition; the tTTF molecules in stacks are grouped into weakly interacting tetramers. The reorganization of tTTF stacks is accompanied with an order-disorder transition in anion sublattice. Polarized infrared and Raman spectra of (tTTF)ClO are measured in the broad frequency range as a function of the temperature (10-293 K). The structural and vibrational features are investigated to elucidate the origin of the semiconductor-semiconductor phase transition. We discuss the electron-intramolecular vibration coupling effects in the vibrational spectra of (tTTF)ClO and identify signatures of high- and low-temperature states of charge localization in the tetramerized system. Both the C=C and C-S stretching modes of tTTF give evidence of strong charge distribution fluctuations in conducting stacks for T  >  137 K, which are responsible for the appearance of molecules with charge  +1e, and charge localization in tTTF tetramers for T  <  137 K. The uniqueness of the salt (tTTF)ClO in comparison with other tetramerized 1D systems is discussed. %G English %2 https://univ-rennes.hal.science/hal-02015713/document %2 https://univ-rennes.hal.science/hal-02015713/file/Fr%C4%85ckowiak%20et%20al.%20-%202019%20-%20Charge%20localization%20in%20one-dimensional%20tetramerize.pdf %L hal-02015713 %U https://univ-rennes.hal.science/hal-02015713 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ ENSC-RENNES %~ ISCR %~ SCR_MACSE %~ STATS-UR1 %~ UR1-SPM %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ UR1-SDLM %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ TEST-HALCNRS %~ UR1-MMS %~ TEST2-HALCNRS