在无机晶体结构数据库 (ICSD) 中搜索缺失的对称性
1Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia.
概括
对无机晶体结构数据库 (ICSD) 的详尽搜索显示,0.65%的条目表现出比最初报告的更高的对称性. 这一发现影响了对材料特性的理解,并建议对晶体结构数据进行改进.
科学领域:
- 晶体学和材料科学 材料科学
- 固态化学 固态化学
- 数据库策划数据库策划
背景情况:
- 无机晶体结构数据库 (ICSD) 是晶体学数据的关键资源.
- 准确的空间组分配对于理解和预测材料性质至关重要.
- 之前的分析并没有对大型ICSD数据集进行全面的对称性重新评估.
研究的目的:
- 系统地搜索和识别ICSD中可能比目前报告的对称性更高的条目.
- 评估纠正对称性赋值对材料属性的影响,特别是非中心对称性.
- 建议对ICSD进行改进,以提高数据的准确性和实用性.
主要方法:
- 在ICSD (2023-2版本) 中对223,076条条目进行了详尽的对称性搜索.
- 分析已识别的条目,以确定是否适用更高对称性描述.
- 研究了受影响项目的非中心对称和中心对称空间组分配之间的关系.
主要成果:
- 在分析的ICSD条目中,大约有0.65%可以通过更高的对称性来描述.
- 在被确定为非中心对称的条目中,大约有74%可以被中心对称的空间组准确地描述.
- 这些对称差异对预测和理解材料相容的物理性质有重大影响.
结论:
- 值得注意的是,ICSD条目中的很少一部分可能会被报告为低于最佳对称度,这会影响材料科学研究.
- 可重新归类为中心对称的非中心对称条目的高百分比凸显了对称性确定中的潜在错误.
- 建议将有关正确的,最高可能的空间组的信息纳入ICSD以提高数据完整性.
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