Premium
Modeling high pressure reactivity in unsaturated systems: Application to dimethylacetylene
Author(s) -
Mediavilla C.,
Tortajada J.,
Baonza V. G.
Publication year - 2009
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.21068
Subject(s) - cyclobutadiene , intermolecular force , reactivity (psychology) , dimer , chemistry , phase (matter) , molecule , computational chemistry , thermodynamics , materials science , organic chemistry , physics , medicine , alternative medicine , pathology
Abstract A general model is introduced to study pressure‐induced reactivity on unsaturated systems in the condensed state. The model is applied here to dimethylacetylene (DMA) in the solid phase II (C/2m) because it has been proposed that two DMA molecules can react to form tetramethyl‐cyclobutadiene (TMCBD). The proposed reaction process has been modeled by studying the structural and electronic changes undergone by two DMA molecules as they approach each other preserving the crystal symmetry of phase II. Both monodeterminantal (MP2 and DFT) and multideterminantal (CASSCF and MRMP2) methodologies were used to check the reliability of our model in predicting the reactivity of the system under compression. In all cases, structural results are in agreement with low‐temperature diffraction experiments for the solid phase II. Our model indicates that DMA is expected to form the TMCBD dimer at intermolecular distances close to 2 Å. This value is in excellent agreement with previous calculations on the existence of long carbon–carbon bonds. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009