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CO₂的债券分离能量具有光谱精度,使用国家对国家分辨的值碎片收益率光谱

Shiyan Gong¹, Peng Wang¹, Yuxiang Mo¹

¹Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China.

The journal of physical chemistry letters

|October 22, 2024

概括

我们精确测量了二氧化碳 (CO2) 的键解离能为 43976.12 cm-1. 这些准确的数据为二氧化碳分子和量子化学计算提供了关键的基准.

科学领域:

化学物理化学物理
分子光谱学分子光谱学
量子化学是一个量子化学.

背景情况:

准确的键解离能是理解分子稳定性和化学反应的基础.
之前对二氧化碳 (CO2) 的测量缺乏高水平理论基准所需的精度.

研究的目的:

为了准确地确定CO2的键解离能,用于CO2 → CO + O通道.
计算二氧化碳分解为C+O2的能量和二氧化碳原子化能量.
为分子能量的理论计算建立新的基准.

主要方法:

使用的州对州的解决值碎片收益率谱.
在波长约为92纳米的波长中使用光刺激.
综合先前测量的CO和O2的键解离能.

主要成果:

确定了二氧化碳的键解离能 (CO2 → CO + O) 为 43976.12(15) cm−1 (526.0714(18) kJ/mol).
计算了二氧化碳分解为C+O2的能量为92309.73(21) cm−1 (1104.2699(25) kJ/mol).
确定了CO2的原子化能量 (CO2 → C + O + O) 在133578.92(18) cm-1 (1597.9592(22) kJ/mol).

结论:

对于所有二氧化碳键解离能量通道,已达到0.2 cm-1或0.002 kJ/mol的不确定性.
这些精确的值作为C原子,CO和CO2分子的度的关键参考点.
结果提供了严格的基准,用于验证先进的ab initio量子化学计算.

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