title: [Research on the spectral analysis and stability of copper green].
abstract: In the history of Chinese pigment, copper green, a pigment, was used in vast territory and for a long time. In the present paper, the nature, spectral characteristics, thermodynamic stability of the four isomers of the basic copper chlorides and also their application in the polychrome relics were discussed. The four isomers can be identified quickly by Raman spectral analysis which is a micro-damage or even a nondestructive technique. The order of their thermodynamic stability is as follows: clinoatacamite>paratacamite>atacamite>botallackite. It was showed that in the relics samples copper green was mostly botallackite and atacamite which were less stable isomers. According to the Ostwald step rule, the environmental monitoring should be strengthened to prevent the change in their physical and chemical structures.
authors.affiliation: College of Cultural Heritage, Northwest University, Xi'an 710069, China. 895843503@qq.com
authors.forename: Man
authors.initials: M
authors.lastname: Li
authors.affiliation: College of Cultural Heritage, Northwest University, Xi'an 710069, China.
authors.forename: Li-Qin
authors.initials: LQ
authors.lastname: Wang
authors.affiliation: Key Scientific Research Base of Ancient Polychrome Pottery Conservation, SACH, Emperor Qinshihuang's Mausoleum Site Museum, Lintong 710600, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Key Scientific Research Base of Masonry Relics Conservation, Research Institute of Shaanxi Cultural Relics Conservation, Xi'an 710075, China.
authors.forename: Qiu-Ying
authors.initials: QY
authors.lastname: Yang