Table 1

Comparison of observed [44] and calculated lattice parameters and atomic positions for bulk α-FeOOH.


Experimental
Calc1
Calc2
Calc3

a
9.95
9.94
9.95
9.95
b
3.01
2.99
3.00
3.00
c
4.62
4.60
4.60
4.60
α = β = γ
90
90
90
90
O1
.05, .75, .20
.05, .75, .20
.05, .75, .20
.06, .75, .20
O2
.20, .75, .71
.20, .75, .71
.20, .75, .70
.20, .75, .68
O3
.30, .25, .22
.30, .25, .21
.30, .25, .20
.30, .25, .19
O4
.45, .25, .70
.45, .25, .70
.45, .25, .70
.44, .25, .70
O5
.55, .75, .30
.55, .75, .30
.55, .75, .30
.56, .75, .30
O6
.70, .75, .78
.70, .75, .79
.70, .75, .80
.70, .75, .82
O7
.80, .25, .28
.80, .25, .29
.80, .25, .30
.80, .25, .32
O8
.95, .25, .80
.95, .25, .80
.95, .25, .80
.94, .25, .80
Fe1
.15, .25, .95
.15, .25, .96
.15, .25, .96
.15, .25, .94
Fe2
.35, .75, .45
.35, .75, .46
.35, .75, .46
.35, .75, .44
Fe3
.65, .25, .55
.65, .25, .54
.65, .25, .54
.65, .25, .56
Fe4
.85, .75, .05
.85, .75, .04
.85, .75, .05
.85, .75, .06
H1
.10, .75, .40
.08, .75, .41
.08, .75, .40
.09, .75, .40
H2
.40, .25, .90
.42, .25, .91
.42, .25, .90
.41, .25, .90
H3
.60, .75, .10
.58, .75, .09
.58, .75, .09
.59, .75, .10
H4
.90, .25, .60
.92, .25, .59
.92, .25, .59
.91, .25, .60

Calc1 = 1 × 1 × 1 unit cell; Calc2 = 1 × 3 × 2 supercell; Calc3 = 1 × 3 × 2 supercell with SP-GGA+U correction.

Kubicki et al. Geochemical Transactions 2008 9:4   doi:10.1186/1467-4866-9-4