Mg
O
H

Brucite

Brucite, Mg(OH)2, is a member of the oxides and hydroxides family. It has a monoclinic crystal system with tabular habit. It is not an important mineral in soils, per se, but it presents a model system for a trioctahedral sheet structure that is not attached to a silicate tetrahedral sheet as in the trioctahedral phyllosilicates. Its dioctahedral corollary is gibbsite, Al(OH)3

Crystallographic Data

Composition

Mg(OH)2

Classification

Trioctahedral Hydroxide

Structural parameters

a=3.073, b=3.073, c=4.496 Å
alpha=90, beta=90, gamma=120°
Space Group: P-3m

atom

x/a

y/b

z/c

H 0.389 0.778 0.435
O 0.3333 0.6667 0.232
Mg 0.000 0.000 0.000

Reference

Parise, J.B., K. Leinenweber, D.J. Weidner, K. Tan, and R.B. Von Dreele. 1994. Pressure-induced H bonding: neutron diffraction study of brucite, Mg (OD)2, to 9.3 GPa. American Mineralogist. 79:193-196.

Parise J.B., K. Leinenweber, D.J. Weidner, K. Tan, and R.B. Von Dreele. 1994. Pressure-induced H bonding: neutron diffraction study of brucite, Mg (OD)2, to 9.3 GPa. American Mineralogist79:193-196