Introduction to the theory of electronic non-adiabatic coupling terms in molecular systems

摘要: Abstract The Born–Oppenheimer treatment leads to the adiabatic framework where non-adiabatic terms are physical entities responsible for coupling between states. main disadvantage of this is in fact that these frequently become singular thus causing difficulties solving relevant Schroedinger equation motion nuclei make up molecular systems. In review, we present line integral approach which enables formation adiabatic-to-diabatic transformation matrix yields friendlier diabatic framework. review concentrates on mathematical conditions allow rigorous derivation and its interesting properties. One findings study have be quantized a certain manner order yield single-valued potentials. Another important feature revealed existence topological matrix, contains all features given system related closed contour configuration space. Finally, an approximation results from which, contrast original approximation, effect terms. various derivations accompanied by examples many cases themselves.