Card No: 3330       Created: 23/10/1989    Last edition: 20/04/2017

Name: OMPHACITE
Specification: [1], structure type - omphacite
Formula: (Ca,Na)(Mg,Al,Fe)Si2O6
Symmetry Class: monoclinic-beta
Space Group: P 2/n
Unit Cell
Parameters:
a = 9.5780 | b = 8.7720 | c = 5.2530 | beta = 106.8900
Number of Formula Unit: Z = 4Unit Cell Volume, Å3: Vc = 422.31
Number of Atomic Position
per full Unit Cell
:
P/U = 40 Molar Volume, cm3/mol: Vm = 63.59
Number of Reflexes used in
Structure Determination
:

NR = 1012
X-ray density, g/cm3: p = 3.32
R-factor: R = 0.0390MU, 1/cm: µ = 219.653
Wave Length for Calculated
Powder Diffraction Patterns
:
Co=1.78892Mass attenuation coefficient,
cm2/g
:
µ/p = 66.111
Theta-Interval for CPDP: T/I = 1-45