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Based on the ab initio/6-31G~* calculation, the potential barrier to internal rotation in mol-ecule H_3N--BH_3 has been studed by means of PD/LSF atomic charge model and Buckingham(exp--6-1)energy partition method. The results indicate that the order of the contributions of the componentsto the total energy barrier △E is |△V_(es)|(electrostatic) >|△V_(et)| (charge transfer)>|△V_(ex)| (exchangerepulsion)>|△V_(di)| (dispersion). For △V_(es) there are maxima at θ= 30°and 90°, and a saddle atθ= 60°. There are good linear relationships for the total barrier △E, △V_(ex) and △V_(di) with cos3θrespectively, and the same for the dipole moment from PD/LSF model (μ_(PD)) and that from abinitio calculation (μ_(QM)) vs. cos3θ respectively.
Based on the ab initio / 6-31G ~ * calculation, the potential barrier to internal rotation in mol-ecule H_3N - BH_3 has been studed by means of PD / LSF atomic charge model and Buckingham (exp - 6-1) energy partition method. The results indicate that the order of the contributions of the component of the total energy barrier ΔE is | ΔV_es (electrostatic)> | ΔV_ (et) | (charge transfer)> | ΔV_ (ex There are maxima at θ = 30 ° and 90 °, and a saddle atθ = 60 °. There are good linear relationships for the total barrier ΔE, ΔV_ex and ΔV_ di with cos3θrespectively, and the same for the dipole moment from PD / LSF model (μ_ (PD)) and that from ab initio calculation (μ_ (Q_m)) vs. cos3θ respectively.