Ab initio study of secondary isotope effects on molecular structure
نویسندگان
چکیده
An ab initio calculation of a secondary isotope effect on a bond length has been carried out for the first time. Single determinant molecular orbital computations indicate that the mean C-C bond length at O"K is longer in C,H6 than in C,D6 by 0.0015 A. A comparison with model calculations supports a steric interpretation in which H atoms act as if they are bulkier than 0 atoms owing to their larger bending amplitudes of vibration.
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