%0 Journal Article %T Competing stacking modes in crystals of trihalogeno-trimethyl-benzene Theory meets experiment %+ Institut des Sciences Chimiques de Rennes (ISCR) %A Meinnel, J. %A Amar, A. %A Boucekkine, A. %A Jeannin, O. %A Camerel, F. %A Barrière, F. %Z We acknowledge the HPC resources of CINES and of IDRIS under the allocations 2017 and 2018 [x2016080649] made by GENCI (Grand Equipement National de Calcul Intensif). %< avec comité de lecture %@ 0022-0248 %J Journal of Crystal Growth %I Elsevier %V 515 %P 1-8 %8 2019-06 %D 2019 %R 10.1016/j.jcrysgro.2019.03.006 %K A1-Computer simulation %K A1-Crystal structure %K A1-Growth models %K A2-Growth from solutions %K A2-Single crystal growth %K B1-Aromatic compounds %Z Chemical SciencesJournal articles %X The special case of the stacking of trihalogeno mesitylene (TXM) molecules has been investigated. Below 300 K, these molecules lead to needle shaped crystals in a triclinic arrangement. Thanks to DFT computations and an empirical atom-atom interaction model this packing mode has been rationalized. Aggregates of TXM molecules differently packed have been considered, namely dimers and trimers of type A, the molecules being piled one over the other along the axis a, and dimers B and trimers B, the molecules lying in the same bc plane. From the computations, it appears that the stabilizing energy of formation of a dimer of two molecules piled along a is several times larger than the energy gain obtained from the formation of a dimer of two neighbors in the bc plane. It has also been found that the energy of formation of a trimer of type A is approximately twice the energy of formation of a dimer A, so that an additive rule occurs. These conclusions are in perfect agreement with the experimental observations of the shape of the crystals obtained by crystallization from a super-saturated solution of TXM in an organic solvent long needles with TXM molecules stacked along the axis a have always been obtained and never thin plate-like crystals. © 2019 Elsevier B.V. %G English %2 https://univ-rennes.hal.science/hal-02090000/document %2 https://univ-rennes.hal.science/hal-02090000/file/Meinnel_et_al-2019-Competing_Stacking_Modes_in_Crystals_of_Trihalogeno-Trimethyl-Benzene.pdf %L hal-02090000 %U https://univ-rennes.hal.science/hal-02090000 %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ ENSC-RENNES %~ ISCR %~ SCR_MACSE %~ ISCR-CTI %~ STATS-UR1 %~ UR1-SPM %~ GENCI %~ INC-CNRS %~ UR1-UFR-SPM %~ UR1-HAL %~ UR1-SDLM %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ TEST-HALCNRS %~ UR1-MMS %~ TEST2-HALCNRS