A vibrational spectroscopic study of the arsenate minerals cobaltkoritnigite and koritnigite

作者：Frost Ray L^*; Lopez Andres; Xi Yunfei; Lana Cristiano; Souza Larissa; Scholz Ricardo; Sejkora Jiri; Cejka Jiri

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2014, 125: 313-318.

DOI：10.1016/j.saa.2014.01.106

• Cobaltkoritnigite
• Koritnigite
• Hydrogen-arsenate
• Raman spectroscopy
• Molecular water
• Hydrogen bonds

Raman spectra of two well-defined types of cobaltkoritnigite and koritnigite crystals were recorded and interpreted. Significant differences in the Raman spectra of cobaltkoritnigite and koritnigite were observed. Observed Raman bands were attributed to the (AsO3OH)(2-) stretching and bending vibrations, stretching and bending vibrations of water molecules and hydroxyl ions. Both Raman and infrared spectra of cobaltkoritnigite identify bands which are attributable to phosphate and hydrogen phosphate anions proving some substitution of phosphate for arsenate in the structure of cobaltkoritnigite. The O-H center dot center dot center dot O hydrogen bond lengths in the crystal structure of koritnigite were inferred from the Raman spectra and compared with those derived from the X-ray single crystal refinement. The presence of (AsO3OH)(2-) units in the crystal structure of cobaltkoritnigite and koritnigite was proved from the Raman spectra which supports the conclusions of the X-ray structure analysis.

• 出版日期2014-5-5