AM_Braunite_4 Formula: Mn7 Si O12 Name: Braunite Unit cell: 9.4266 9.4266 18.6952 90.0 90.0 90.0 , V=1661.27 Space group: I41/ACD (142)

Miletich R , Allan D R , Angel R J , Physics and Chemistry of Minerals , 25 (1998) p.183-192, Structural control of polyhedral compression in synthetic braunite,, Mn2+Mn3+6O8SiO4, Sample in Diamond Anvil Cell without pressure medium: P = 0.0001 GPa