电子自由能量表面的阻子使用第一原则有限的温度电子结构方法
William Z Van Benschoten1, Hayley R Petras1, James J Shepherd1
1Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States.
The journal of physical chemistry. A
|August 3, 2023
概括
由于内部能量,二元键随着温度升高而加强,但随着而减弱. 热驱动的解离发生在极高的温度下,在22,000-63,200 K之间.
科学领域:
- 计算化学是一种计算化学.
- 量子力学就是量子力学.
- 材料科学是一种材料科学.
背景情况:
- 二原子分子在高温下的行为对于理解化学反应和材料特性至关重要.
- 二聚合物 (N2) 是一种具有强烈的三重键的基本分子,在理论研究中经常被用作基准.
研究的目的:
- 在不同温度下研究二元体的电子自由能量表面.
- 了解内部能量和对-键强度的相互影响.
- 为了预测二元体的热驱动解离的温度范围.
主要方法:
- 采用了全配置交互 (FCI) 和密度矩阵量子蒙特卡洛 (DMQMC) 方法.
- 计算是在自由能量波恩-奥本海默近似中进行的.
- 在不同的温度和键长度下分析了电子自由能量表面.
主要成果:
- 确定了一个温度状态,其中内部能量导致-键的强化.
- 发现力贡献对于观察高温时的债券减弱至关重要.
- 预计二元体的热驱动解离在22,000K和63,200K之间,受对称性和基础集的影响.
结论:
- 这项研究揭示了在解离之前在中等温度下强化的反直觉纽带.
- 包括空间和旋转对称性显著降低了预测的解离温度.
- 对密度矩阵结构的分析为温度依赖的结合行为提供了洞察力.
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