小分子的热化学性质:ReC,ReN,ReO,ReS和ReC2
Kimberly H Tomchak1, Erick Tieu1, Thomas T Kawagoe1
1Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, USA.
The Journal of chemical physics
|November 18, 2025
概括
这项研究精确测量了使用激光切除方法测量含有的分子如ReC和ReN的键解离能和电离能. 这些发现为化合物提供了关键的热化学数据.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 频谱学是一种光谱学.
背景情况:
- 含的分子由于其独特的化学特性而引起人们的兴趣.
- 准确的热化学数据,如键解离能 (BDE) 和电离能 (IE),对于理解化学键和反应性至关重要.
- 对新型分子的这些特性进行实验性确定往往具有挑战性.
研究的目的:
- 通过实验确定含有的中性分子 (ReC,ReN,ReO,ReS,ReC2) 的精确键解离能 (BDEs) 和电离能 (IEs).
- 计算对应的含的离子 (ReC+,ReN+,ReO+) 的BDE.
- 用各种理论方法进行比较,以计算方式研究电子结构和热化学性质.
主要方法:
- 脉冲激光除超音速束分子源用于产生含分子.
- 共振两光子电离实验与飞行时间质谱学相结合用于检测.
- 精确测量预分离值以确定BDE.
- 测量两光子电离值,以确定IE.
- 密度函数理论 (DFT) 和合集群 (CCSD) 计算用于理论验证.
主要成果:
- 精确的BDE测量了ReC (5.731(3) eV),ReN (5.635(3) eV,ReO (5.510(3) eV,ReS (3.947(3) eV和Re-C2 (5.359(3) eV) 的情况.
- 对于ReC (8.425(12) eV,ReN (8.193(20) eV和ReO (8.561(11) eV) 确定了IE.
- 对于离子ReC+ (5.140(12) eV),ReN+ (5.275(20) eV和ReO+ (4.783(11) eV) 的BDE被导出.
- 来自DFT和CCSDT方法的计算结果通常与实验值相一致.
结论:
- 本研究报告了对这些特定含分子的BDE和IE的首次实验测量.
- 实验和计算数据为这些物种提供了全面的热化学概况.
- 这些发现有助于更好地了解-联体结合和相关化合物的周期趋势.
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