Phase dependence of molecular structures

Structures of the adducts Me3Al-OMe2 and Me3Al SMe2, with values of parameters that are strongly phase-dependent. Two values for solid Me3Al SMe2 are due to two independent molecules in the unit cell. 

The work on decamethylsilicocene was published in two papers, a communication containing just the crystal structure [58] and, three years later, a full paper by the same authors containing the gas-phase study. When they only had the crystal structure they argued that the bent structure of one molecule must be due to weak intermolecular interactions and thus a result of packing. After the ground state in the gas phase was shown to be bent, this argument had to be reversed. 

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