AM_Pyroxene-ideal_136 Formula: Mg Si O3 Name: Pyroxene-ideal Unit cell: 9.002 8.698 5.022 90.0 90.0 90.0 , V=393.22 Space group: P21CN (33)

Thompson R M , Downs R T , American Mineralogist , 89 (2004) p.614-628, Model pyroxenes II: Structural variation as a function of tetrahedral rotation, model hi-P protopx at 9.98 GPa after Yang et al. (1999) with, O3A-O3A-O3A angle = 147.8, O3B-O3B-O3B angle = 220.8, and model oxygen radius = 1.307, Note: Atoms Mg, Si, and O are assigned to atomic positions for convenience