TUNNELING SPLITTINGS FROM AB-INITIO DATA - INDOLINE, A TEST-CASE

A combination of ab initio and semiclassical modeling is used to simul ate the observed tunneling splittings of indoline. Through the Instant on approach and the introduction of effective parameters, the semiclas sical one-dimensional theory is extended to the multidimensional case without loss of simplicity. To avoid a possible bias in the derivation of the input parameters, the corrections for the effective mass and t he effective potential are obtained ab initio at the standard HF/6-31G level. This framework, which is highly sensitive to the input parame ters, successfully reproduces all the observed splittings. Reasons for the success of the present formulation are briefly discussed.