...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Quantum-mechanical calculations of the stabilities of fluxional isomers of C4H7+ in solution
【24h】

Quantum-mechanical calculations of the stabilities of fluxional isomers of C4H7+ in solution

机译：溶液中C4H7 +的通量异构体稳定性的量子力学计算

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

Although numerous quantum calculations have been made over the years of the stabilities of the fluxional isomers of C4H7+, none have been reported for other than the gas phase (which is unrealistic for these ionic species) that exhibit exceptional fluxional properties in solution. To be sure, quantum-mechanical calculations for solutions are subject to substantial uncertainties, but nonetheless it is important to see whether the trends seen for the gas-phase C4H7+ species are also found in calculations for polar solutions. Of the C4H7+ species, commonly designated bisected-cyclopropylcarbinyl 1, unsym-bicyclobutonium-2, sym-bicyclobutonium 3, allylcarbinyl 4, and pyramidal structure 6, the most advanced gas-phase calculations available thus far suggest that the order of stability is 1 > 2 greater than or equal to 3 greater than or equal to 4 greater than or equal to 6 with barriers of only -1 kcal/mol for interconversions among 1, 2, and 3. We report here that, when account is taken of solvation, 2 turns out to be slightly more stable than 1 or 3 in polar solvents. The pattern of the overall results is unexpected, in that despite substantial differences in structures and charge distributions between the primary players in the C4H7+ equilibria and the large differences in solvation energies calculated for the solvents considered, the differential solvent effects from species to species are rather small. [References: 23]
机译：尽管多年来对C4H7 +的通量异构体的稳定性进行了大量的量子计算，但除了气相（对于这些离子种类而言这是不现实的）以外，在溶液中表现出优异的通量特性的其他研究均未见报道。可以肯定的是，溶液的量子力学计算存在很大的不确定性，但是，重要的是要了解在极性溶液的计算中是否还发现了气相C4H7 +的趋势。在C4H7 +物种中，通常指定为对分的-环丙基羰基1，非对称双环丁鎓2，对称双环丁鎓3，烯丙基羰基4和锥体结构6，迄今为止最先进的气相计算表明稳定性的顺序为1> 2大于或等于3大于或等于4大于或等于6，且1、2和3之间的相互转换势垒仅为-1 kcal / mol。我们在此报告，考虑到溶剂化，在极性溶剂中，2比1或3稳定。总体结果的模式是出乎意料的，因为尽管C4H7 +平衡的主要参与者之间在结构和电荷分布上存在实质性差异，并且对于所考虑的溶剂计算出的溶剂化能存在很大差异，但不同物种之间的差异溶剂效应相当小。 [参考：23]

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