New perspective of chemical bond by the spin-symmetrized Hartree-Fock method

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K05371
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 32010:Fundamental physical chemistry-related
• Research Institution: Kanazawa University
• Principal Investigator: IDA tomonori 金沢大学, 物質化学系, 准教授 (30345607)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 化学結合 / 電子基底状態 / Coulson-Fischer波動関数 / 水素分子

Outline of Final Research Achievements

In 1985, Luzanov proposed a theoretical development called the spin-symmetrized Hartree-Fock equation, which has not progressed well. We examined this equation closely and found that it is identical to the wavefunction proposed by Coulson and Fischer in 1949, which has the characteristics of both the VB and MO methods. The Coulson-Fischer wavefunction had been developed by Wilson as the modern VB method, but the originality of the calculation method was too strong that other researchers could not easily use it. Therefore, we investigated the theory from the viewpoint of the MO method and established a formulation that can be calculated with existing MO software. Furthermore we demonstrated a high-precision calculation for the electronic ground state of a hydrogen molecule by using the formulation.

Free Research Field

理論化学

Academic Significance and Societal Importance of the Research Achievements

これまで水素分子の電子基底状態は様々な理論によって表現されてきたが、申請者の提案する計算手法は、既に多くの研究者によって考察されたVB法とMO法の両方の特徴を併せ持ち、かつ誰でもその波動関数を利用可能とするために改良を施した。得られる波動関数には化学結合に関する新しい見方も含まれており、波動関数の研究としても興味深い。またこの波動関数は様々な計算手法（密度汎関数法など）へ応用が可能であり、加えて高次電子相関計算の基底状態としても利用できる。この様に考案された計算手法は多岐の分野への応用が期待される。