基于其实验电荷密度的N(2) O(4) 的原子性质
Marc Messerschmidt1, Armin Wagner, Ming Wah Wong
1Institute for Chemistry/Crystallography, Free University Berlin, Takustrasse 6, 14195 Berlin, Germany.
Journal of the American Chemical Society
|January 31, 2002
概括
这项研究表明,二氧化 (N2O4) 晶体中的长N-N键具有约0.5.5的键序. 实验和理论原子体积密切匹配,尽管理论计算考虑了孤立的分子.
科学领域:
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 量子化学是一种量子化学.
背景情况:
- 氧化二四氧化物 (N2O4) 存在于其晶体形式的二元体中,具有特别长的N-N键.
- 了解这种键的电子结构对于化学键理论至关重要.
研究的目的:
- 通过实验确定晶体N2O4.4的电荷密度分布和原子性质.
- 将实验结果与各种原子电荷和体积的理论计算进行比较.
- 在N2O4.4.中调查长N-N债券的债券顺序.
主要方法:
- 使用CCD区域探测器进行低温结晶和X射线衍射.
- 采集高分辨率数据以产生实验性电荷密度.
- 在分子中应用贝德的原子 (AIM) 理论来计算零流量表面.
- 实验数据与使用Mulliken,AIM,NPA和CHELP方法的理论计算进行比较.
主要成果:
- 对晶体N2O4.4的试验电荷密度分布成功生成.
- 从实验中获得的原子体积与理论计算有很强的一致性.
- AIM收费证明与所选择的基础组独立.
- 通过与模型化合物进行比较,估计长N-N债券的债券订单约为0.5.
结论:
- 这项研究证实了理论方法在预测原子体积方面的准确性,即使是与孤立分子相比,晶体固体也是如此.
- 在N2O4中长N-N键表现出低键序,表明相互作用较弱.
- 实验性电荷密度分析为分子晶体中结合的性质提供了宝贵的见解.
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