黑马的颜色重新审视:颗粒大小和电子转换
Isabela F S Dos Santos1, Howell G M Edwards2, Dalva L A de Faria3
1Paulista Museum, University of São Paulo, 04263-000 São Paulo - SP, Brazil; Institute of Chemistry, University of São Paulo, 05508-000 São Paulo - SP, Brazil.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
|January 17, 2024
概括
血是一种颜料,它的紫色来源于其结晶性,而不是颗粒大小. 这种结晶性改变了光吸收,特别是在500nm以下,创造了独特的深色调.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 频谱学是一种光谱学.
背景情况:
- 黑马 (α-Fe2O3) 是一种广泛使用的天然颜料,以其颜色范围而闻名.
- 紫色的品种,caput mortuum,历史上一直被归因于粒子大小.
- 了解其颜色的起源对于颜料应用至关重要.
研究的目的:
- 为了调查血中紫色的起源.
- 为了区分粒子大小和结晶性作为紫色的原因.
- 为了阐明负责颜色的光学机制.
主要方法:
- 扩散反射光谱 (DRS) 用于光学特性.
- 用能量分散光谱扫描电子显微镜 (SEM-EDS) 检测形态和组成.
- 拉曼显微镜用于结构和振动分析.
主要成果:
- 紫色血的颜色与结晶性有关,而不是颗粒大小.
- 结晶性导致500nm以下的吸收减少,并在880nm左右增强d-d过渡.
- 扭曲的FeO6八面体可能会影响氧到铁的电荷转移过渡.
结论:
- 血的紫色主要是由于其晶体结构.
- 在FeO6八面体中的结构扭曲在观察到的光学特性中起着重要作用.
- 需要进一步的实验来确认电荷转移过渡的确切作用.
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