Fe(AsO4)·2H2O was obtained hydrothermally from an aqueous solution of iron(III) chloride, ethylenediamine and arsenic acid. The structure features six-coordinate iron with sulfate anions acting as bridging ligands.
Supporting information
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (e-O) = 0.003 Å
- R factor = 0.024
- wR factor = 0.059
- Data-to-parameter ratio = 10.6
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 0.94
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........ 4
Alert level G
ABSTM02_ALERT_3_G When printed, the submitted absorption T values will be
replaced by the scaled T values. Since the ratio of scaled T's
is identical to the ratio of reported T values, the scaling
does not imply a change to the absorption corrections used in
the study.
Ratio of Tmax expected/reported 0.936
Tmax scaled 0.293 Tmin scaled 0.243
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature . 293 K
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
2 ALERT level C = Check and explain
3 ALERT level G = General alerts; check
2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
0 ALERT type 2 Indicator that the structure model may be wrong or deficient
1 ALERT type 3 Indicator that the structure quality may be low
2 ALERT type 4 Improvement, methodology, query or suggestion
0 ALERT type 5 Informative message, check
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL.
iron(III) arsenate dihydrate
top
Crystal data top
Fe(AsO4)·2H2O | F(000) = 888 |
Mr = 230.80 | Dx = 3.291 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 4587 reflections |
a = 8.942 (7) Å | θ = 3.6–26.0° |
b = 10.075 (8) Å | µ = 10.23 mm−1 |
c = 10.339 (8) Å | T = 293 K |
V = 931.5 (12) Å3 | Block, green |
Z = 8 | 0.15 × 0.12 × 0.12 mm |
Data collection top
Bruker APEX2 CCD diffractometer | 915 independent reflections |
Radiation source: fine-focus sealed tube | 805 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
ω scans | θmax = 26.0°, θmin = 3.6° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | h = −11→9 |
Tmin = 0.259, Tmax = 0.313 | k = −12→11 |
4587 measured reflections | l = −12→12 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.024 | Only H-atom coordinates refined |
wR(F2) = 0.059 | w = 1/[σ2(Fo2) + (0.0271P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.12 | (Δ/σ)max < 0.001 |
915 reflections | Δρmax = 0.79 e Å−3 |
86 parameters | Δρmin = −0.52 e Å−3 |
4 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0074 (5) |
Special details top
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F2, conventional
R-factors R are based on F, with F set to zero for
negative F2. The threshold expression of F2 >
σ(F2) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F2 are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
As1 | 0.03548 (4) | 0.13613 (4) | 0.15181 (3) | 0.00784 (16) | |
Fe1 | 0.14664 (6) | −0.18243 (6) | 0.12664 (5) | 0.00875 (18) | |
O1 | 0.0069 (3) | −0.0295 (3) | 0.1428 (2) | 0.0109 (6) | |
O2 | 0.2139 (3) | 0.1654 (3) | 0.1093 (3) | 0.0129 (6) | |
O3 | 0.0037 (3) | 0.1951 (3) | 0.3012 (3) | 0.0123 (6) | |
O4 | −0.0834 (3) | 0.2159 (3) | 0.0511 (2) | 0.0139 (6) | |
O1W | 0.2293 (3) | −0.1175 (3) | 0.3004 (3) | 0.0143 (6) | |
H1WA | 0.189 (5) | −0.153 (4) | 0.365 (3) | 0.021* | |
H1WB | 0.321 (2) | −0.108 (4) | 0.319 (4) | 0.021* | |
O2W | 0.3285 (3) | −0.0701 (3) | 0.0547 (3) | 0.0181 (6) | |
H2WA | 0.359 (5) | −0.093 (5) | −0.018 (2) | 0.027* | |
H2WB | 0.315 (5) | 0.0120 (17) | 0.063 (5) | 0.027* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
As1 | 0.0082 (2) | 0.0061 (3) | 0.0092 (2) | 0.00017 (13) | 0.00019 (14) | −0.00045 (14) |
Fe1 | 0.0091 (3) | 0.0076 (3) | 0.0096 (3) | 0.0001 (2) | 0.0001 (2) | −0.0002 (2) |
O1 | 0.0099 (12) | 0.0058 (15) | 0.0170 (15) | 0.0002 (10) | 0.0017 (10) | 0.0000 (11) |
O2 | 0.0101 (13) | 0.0096 (15) | 0.0190 (14) | −0.0021 (10) | 0.0031 (11) | −0.0022 (11) |
O3 | 0.0167 (13) | 0.0106 (15) | 0.0098 (14) | 0.0016 (10) | −0.0001 (11) | −0.0027 (11) |
O4 | 0.0165 (13) | 0.0129 (15) | 0.0121 (13) | 0.0055 (11) | −0.0048 (12) | −0.0022 (11) |
O1W | 0.0121 (13) | 0.0177 (16) | 0.0132 (14) | −0.0034 (11) | −0.0014 (12) | 0.0012 (12) |
O2W | 0.0215 (15) | 0.0083 (15) | 0.0246 (16) | −0.0004 (11) | 0.0069 (13) | 0.0002 (13) |
Geometric parameters (Å, º) top
As1—O3 | 1.679 (3) | Fe1—O2W | 2.116 (3) |
As1—O2 | 1.681 (3) | O2—Fe1iv | 1.984 (3) |
As1—O4 | 1.691 (3) | O3—Fe1v | 1.971 (3) |
As1—O1 | 1.690 (3) | O4—Fe1i | 1.952 (3) |
Fe1—O4i | 1.952 (3) | O1W—H1WA | 0.84 (4) |
Fe1—O3ii | 1.971 (3) | O1W—H1WB | 0.85 (2) |
Fe1—O1 | 1.991 (3) | O2W—H2WA | 0.84 (2) |
Fe1—O2iii | 1.984 (3) | O2W—H2WB | 0.84 (2) |
Fe1—O1W | 2.050 (3) | | |
| | | |
O3—As1—O2 | 109.83 (12) | O2iii—Fe1—O1W | 95.70 (11) |
O3—As1—O4 | 106.94 (13) | O4i—Fe1—O2W | 89.07 (12) |
O2—As1—O4 | 110.63 (14) | O3ii—Fe1—O2W | 172.62 (11) |
O3—As1—O1 | 111.97 (13) | O1—Fe1—O2W | 95.63 (12) |
O2—As1—O1 | 107.61 (12) | O2iii—Fe1—O2W | 84.16 (12) |
O4—As1—O1 | 109.88 (13) | O1W—Fe1—O2W | 81.97 (12) |
O4i—Fe1—O3ii | 92.92 (11) | As1—O1—Fe1 | 132.34 (15) |
O4i—Fe1—O1 | 91.78 (11) | As1—O2—Fe1iv | 135.11 (15) |
O3ii—Fe1—O1 | 91.41 (12) | As1—O3—Fe1v | 133.25 (15) |
O4i—Fe1—O2iii | 87.91 (11) | As1—O4—Fe1i | 132.80 (15) |
O3ii—Fe1—O2iii | 88.81 (13) | H1WA—O1W—H1WB | 106 (5) |
O1—Fe1—O2iii | 179.63 (11) | Fe1—O2W—H2WA | 115 (3) |
O4i—Fe1—O1W | 169.93 (11) | Fe1—O2W—H2WB | 112 (3) |
O3ii—Fe1—O1W | 96.54 (11) | H2WA—O2W—H2WB | 115 (5) |
O1—Fe1—O1W | 84.58 (11) | | |
Symmetry codes: (i) −x, −y, −z; (ii) −x, y−1/2, −z+1/2; (iii) −x+1/2, y−1/2, z; (iv) −x+1/2, y+1/2, z; (v) −x, y+1/2, −z+1/2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O2W—H2WB···O2 | 0.84 (2) | 1.85 (3) | 2.645 (5) | 157 (2) |
O1W—H1WA···O4ii | 0.84 (4) | 1.84 (4) | 2.622 (4) | 154 (4) |
O1w—H1WB···O1vi | 0.85 (2) | 1.88 (3) | 2.701 (4) | 162 (2) |
Symmetry codes: (ii) −x, y−1/2, −z+1/2; (vi) x+1/2, y, −z+1/2. |