(3h) J((15) N-(31) P) 跨N[键]H....O[键]P键的旋转-旋转合常量
Janet E Del Bene1, S Ajith Perera, Rodney J Bartlett
1Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA. fr042008@ysub.ysu.edu
Journal of the American Chemical Society
|May 30, 2002
概括
运动方程合集群计算显示,通过键的-15到-31三键合常量是可测量的,并且在线性排列中取决于距离,从而使结构确定成为可能.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 频谱学是一种光谱学.
背景情况:
- 核磁共振 (NMR) 光谱学为分子结构和结合提供了宝贵的见解.
- 跨过键的三键 (15) N-(31) P 合常量 ((3h) J (((N[键] P)) 是分子几何学的敏感探针.
- 了解这些合可以帮助确定结系统中的距离.
研究的目的:
- 为了研究N-H...O-P键之间的三键 (15) N-(31) P合常量的大小和行为.
- 探索分子几何学 (线性与非线性) 对这些合常数的影响.
- 评估使用 (3h) J(N[键]P) 在键复合体中确定N-P和N-O距离的可能性.
主要方法:
- 使用运动方程合集群单双 (EOM-CCSD) 计算.
- 计算是在具有N-H...O-P键的模拟阴离子和阴离子复合体上进行的.
- 研究了各种结构,包括P(V) 和P(III) 种,以及线性和非线性安排.
主要成果:
- 三键 (15) N-(31) P 合常数对于 P ((V) 是显著的,但对于 P ((III) 是可以忽略不计的.
- 对于非线性 (循环或开放) 结构来说, (3h) J ((N[bond] P) 值通常小于1 Hz.
- 在线或近线布局中观察到较大的 (3h) J ((N[bond] P) 值,尽管N-P距离较长.
结论:
- 费米接触项在线性复合体中显著影响 (3h) J(N[bond]P),并且取决于距离.
- 实验测量 (15) N-(31) P 合常数可用于确定线性系统中的 N-P 和结 N-O 距离.
- 这种方法为特定的键分子系统的结构阐明提供了一种新的方法.
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