Card No: 61       Created: 14/10/1997    Last edition: 13/01/2009

Name: AKERMANITE
Specification: [9], structure type - melilite, at 2.78 GPa
Formula: Ca2MgSi2O7
Symmetry Class: tetragonal
Space Group: P 4(-)2(1)m
Unit Cell
Parameters:
a = 7.7677 | c = 4.9495
Number of Formula Unit: Z = 2Unit Cell Volume, Å3: Vc = 298.64
Number of Atomic Position
per full Unit Cell
:
P/U = 24 Molar Volume, cm3/mol: Vm = 89.94
Number of Reflexes used in
Structure Determination
:

NR = 605
X-ray density, g/cm3: p = 3.03
R-factor: R = 0.0350MU, 1/cm: µ = 206.956
Wave Length for Calculated
Powder Diffraction Patterns
:
Cu=1.54056Mass attenuation coefficient,
cm2/g
:
µ/p = 68.283
Theta-Interval for CPDP: T/I = 1-45