Andrew Liehr and the structure of Jahn-Teller surfaces

23rd International Symposium on the Jahn-Teller Effect

Chibotaru, Liviu F.^1 ; Iwahara, Naoya^1

Theory of Nanomaterials Group, Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, Leuven

3001, Belgium^1

关键词: Adiabatic potential energy surface;    Conformational stabilities;    Jahn-Teller problem;    Jahn-Teller system;    Minimax principle;    Orbital degeneracy;    Static Jahn-Teller;    Vibronic coupling;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/833/1/012008/pdf
DOI  :  10.1088/1742-6596/833/1/012008

来源: IOP

【 摘 要 】

The present article is an attempt to draw attention to a seminal work by Andrew Liehr "Topological aspects of conformational stability problem" [1, 2] issued more than half century ago. The importance of this work stems from two aspects of static Jahn-Teller and pseudo-Jahn-Teller problems fully developed by the author. First, the work of Liehr offers an almost complete overview of adiabatic potential energy surfaces for most known Jahn-Teller problems including linear, quadratic and higher-order vibronic couplings. Second, and most importantly, it identifies the factors defining the structure of Jahn-Teller surfaces. Among them, one should specially mention the minimax principle stating that the distorted Jahn-Teller systems tend to preserve the highest symmetry consistent with the loss of their orbital degeneracy. We believe that the present short reminiscence not only will introduce a key Jahn-Teller scientist to the young members of the community but also will serve as a vivid example of how a complete understanding of a complex problem, which the Jahn-Teller effect certainly was in the beginning of 1960s, can be achieved.