• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International Journal of Quantum Chemistry >Ab initio calculations of weakly bonded He_2 and Be_2 molecules by MRCI method with pseudo-natural molecular orbitals
【24h】

Ab initio calculations of weakly bonded He_2 and Be_2 molecules by MRCI method with pseudo-natural molecular orbitals

机译：利用伪自然分子轨道的MRCI方法从头算计算弱结合的He_2和Be_2分子

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The X~1Σg~+ curves of He_2 and Be_2 have been calculated by extrapolating the BSSE corrected MRCI total energies obtained with large Gaussian basis sets, large reference configuration spaces, and pseudo-natural molecular orbitals to an infinite basis. The direct calculated He_2 nonrelativistic dissociation energies (D_e) of 11.0031 K is in excellent agreement with the recent theoretical evaluations, whereas the Be_2 nonrelativistic D_e = 822 cm~(-1) and relativistically corrected D_e = 818 cm~(-1) are in good agreement with most known values including the experimental D_e = 790 ± 30 cm~(-1). An analysis of the configuration structure of Be_2 wave function and calculated vibration spectrum displays unusual type of chemical bond in this molecule and explains a unique form of the Be _2 potential curve. Thus, near the equilibrium point the bond can be classified as a conventional covalent bond, whereas at larger distances, it can be classified as van der Waals interaction. The problems of high precision Be_2 potential curve calculations are also discussed.
机译：He_2和Be_2的X〜1Σg〜+曲线是通过将由大高斯基集，大参考构型空间和拟自然分子轨道获得的BSSE校正的MRCI总能量外推到无限大的基础来计算的。直接计算的He_2非相对论离解能（D_e）为11.0031 K与最近的理论评价非常吻合，而Be_2非相对论离解能D_e = 822 cm〜（-1）和相对论校正D_e = 818 cm〜（-1）在与包括实验D_e = 790±30 cm〜（-1）在内的大多数已知值具有良好的一致性。对Be_2波函数的构型结构和计算出的振动谱的分析显示了该分子中化学键的不同类型，并解释了Be _2电势曲线的独特形式。因此，在平衡点附近，该键可被分类为常规的共价键，而在较大距离处，其可被分类为范德华相互作用。还讨论了高精度Be_2势能曲线计算问题。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号