阿拉贡石晶体的内在结合和神秘扭曲
Pavel N Gavryushkin1,2, Aleksander Rečnik3, Katerina G Donskikh1,2
1Sobolev Institute of Geology and Mineralogy, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
概括
地质阿拉戈尼特晶体表现出类似于生物原体样本的双重密度,挑战了以前的假设. 计算揭示了双胞胎和非双胞胎结构的相似自由能量,解释了观察到的高双胞胎密度.
科学领域:
- 矿物学和结晶学研究.
- 生物矿物化的研究研究.
- 材料科学是一种材料科学.
背景情况:
- 生物原始阿拉贡岩通常被认为具有比地质阿拉贡岩更高的双胞胎密度.
- 之前的研究并没有广泛地比较不同阿拉贡石来源的双胞胎密度.
- 了解阿拉戈尼特的晶体缺陷对于其地质和生物背景至关重要.
研究的目的:
- 为了研究和比较地质和生物原始阿拉贡石样本中的双胞胎密度.
- 探索在阿拉贡石中晶体结构,自由能量和双胞胎形成之间的关系.
- 在地质阿拉贡石中描述新的结晶学特征.
主要方法:
- 单晶X射线衍射 (SCXRD) 用于结构分析.
- 传输电子显微镜 (TEM) 用于微观结构检查.
- 光学显微镜用于缺陷可视化.
- 吉布斯自由能量的热力学计算.
主要成果:
- 地质上的阿拉贡石表现出双重密度,与来自软体动物的生物原始阿拉贡石相美.
- 吉布斯的自由能量计算支持定期结合的阿拉贡岩结构的稳定性.
- TEM揭示了与生长相关的和应变诱导的双边界和堆叠缺陷.
- 在一些地质阿拉贡石样本中观察到独特的状衍射模式,包括扩散散射和Debye弧.
结论:
- 地质和生物原始阿拉贡岩的双重密度之间的区别可能不如以前想象的那么明显.
- 晶体应变和生长条件显著影响阿拉戈尼特的缺陷形成.
- 观察到的奇拉衍射模式表明地质阿拉贡石中的晶体扭曲和误导子粒,这是这个矿物质的新发现.
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