The Study of Crystal Structure on Grossular–Andradite Solid Solution

Minerals

Dengfei Duan¹  Qiang Sun²  Xi Liu²  Xinjian Bao²  Yichuan Wang² 

[1] College of Resources and Environment, Yangtze University, Wuhan 430074, China;Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, Peking University, Beijing 100871, China;

关键词: grossular–andradite;    x-ray diffraction;    bond length;    excess volume;    distortion;   

DOI  :  10.3390/min9110691

来源: DOAJ

【 摘 要 】

The effects of Al³⁺−Fe³⁺ substitution on 10 synthesized garnet samples along the grossular−andradite binary solid solution were investigated using both powder and single-crystal X-ray diffraction. Results showed that cell volume increased with andradite content. Small negative excess volume was observed in the Al-rich samples. By measuring the bond length, polyhedral volume, octahedral distortion parameter (σ), and tetrahedral rotation angle (α), we determined that the distortion occurred on the dodecahedral site. The width of the diffraction peaks was obviously related to the composition of the solid solution. Full width at half maximum of diffraction peaks was used to calculate the microstrain, which may have a relationship with enthalpy of mixing.

【 授权许可】

Unknown