The single-crystal synchrotron study of the high-pressure modification of aluminium oxide hydroxide, δ-AlOOH, confirms the previous structure determination in the space group
P2
_{1}nm, which was based on X-ray powder data [Suzuki, Ohtani & Kamada (2000).
Phys. Chem. Miner. 27, 689–693]. The present study includes the determination of the H-atom parameters, which revealed a strong asymmetric hydrogen bond with an O
O distance of 2.5479 (12) Å. The δ-AlOOH structure is isotypic with that of β-CrOOH and may be considered as a distorted rutile type with all atoms located on mirror planes.
Supporting information
Key indicators
- Single-crystal synchrotron study
- T = 297 K
- Mean (l-O) = 0.001 Å
- R factor = 0.014
- wR factor = 0.041
- Data-to-parameter ratio = 11.9
checkCIF/PLATON results
No syntax errors found
Alert level B
PLAT115_ALERT_5_B ADDSYM Detects Noncrystallographic Inversion ... 100 PerFi
Alert level C
PLAT128_ALERT_4_C Non-standard setting of Space group Pmn21 .... P21nm
Alert level G
ABSMU_01 Radiation type not identified. Calculation of
_exptl_absorpt_correction_mu not performed.
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
correct. If it is not, please give the correct count in the
_publ_section_exptl_refinement section of the submitted CIF.
From the CIF: _diffrn_reflns_theta_max 42.48
From the CIF: _reflns_number_total 262
Count of symmetry unique reflns 262
Completeness (_total/calc) 100.00%
TEST3: Check Friedels for noncentro structure
Estimate of Friedel pairs measured 0
Fraction of Friedel pairs measured 0.000
Are heavy atom types Z>Si present no
0 ALERT level A = In general: serious problem
1 ALERT level B = Potentially serious problem
1 ALERT level C = Check and explain
1 ALERT level G = General alerts; check
0 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
0 ALERT type 3 Indicator that the structure quality may be low
2 ALERT type 4 Improvement, methodology, query or suggestion
1 ALERT type 5 Informative message, check
Data collection: 10A.EXE (Tanaka & Sasaki, 1993); cell refinement: MSC/AFC Diffractometer Control Software
(Molecular Structure Corporation, 1991); data reduction: TEXSAN (Molecular Structure Corporation, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: VESTA (Momma & Izumi, 2006); software used to prepare material for publication: SHELXL97.
Aluminium oxide hydroxide
top
Crystal data top
AlO(OH) | F(000) = 60 |
M_{r} = 59.99 | D_{x} = 3.536 Mg m^{−}^{3} |
Orthorhombic, P2_{1}nm | Synchrotron radiation, λ = 0.7007 (1) Å |
Hall symbol: P -2 2ac | Cell parameters from 56 reflections |
a = 4.7128 (11) Å | θ = 6.4–14.8° |
b = 4.2221 (15) Å | µ = 1.05 mm^{−}^{1} |
c = 2.8315 (7) Å | T = 297 K |
V = 56.34 (3) Å^{3} | Prism, colourless |
Z = 2 | 0.04 × 0.04 × 0.04 mm |
Data collection top
Tsukuba-BL-10A diffractometer | θ_{max} = 42.5°, θ_{min} = 4.8° |
Radiation source: synchrotron | h = −9→9 |
ω/2θ scans | k = −8→8 |
1633 measured reflections | l = −5→5 |
262 independent reflections | 3 standard reflections every 50 reflections |
262 reflections with I > 2σ(I) | intensity decay: none |
R_{int} = 0.034 | |
Refinement top
Refinement on F^{2} | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F^{2} > 2σ(F^{2})] = 0.014 | All H-atom parameters refined |
wR(F^{2}) = 0.041 | w = 1/[σ^{2}(F_{o}^{2}) + (0.0183P)^{2} + 0.0106P] where P = (F_{o}^{2} + 2F_{c}^{2})/3 |
S = 1.33 | (Δ/σ)_{max} < 0.001 |
262 reflections | Δρ_{max} = 0.33 e Å^{−}^{3} |
22 parameters | Δρ_{min} = −0.35 e Å^{−}^{3} |
0 restraints | Extinction correction: SHELXL97, Fc^{*}=kFc[1+0.001xFc^{2}λ^{3}/sin(2θ)]^{-1/4} |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 1.01 (12) |
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 F^{2} against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F^{2}, conventional
R-factors R are based on F, with F set to zero for
negative F^{2}. The threshold expression of F^{2} >
σ(F^{2}) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F^{2} 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 (Å^{2}) top | x | y | z | U_{iso}*/U_{eq} | |
Al1 | 0.0000 | 0.27452 (7) | 0.0000 | 0.00298 (9) | |
O1 | 0.3420 (2) | 0.49850 (17) | 0.0000 | 0.00329 (12) | |
O2 | 0.64559 (19) | −0.00084 (17) | 0.0000 | 0.00356 (13) | |
H1 | 0.547 (13) | 0.157 (8) | 0.0000 | 0.034 (10)* | |
Atomic displacement parameters (Å^{2}) top | U^{11} | U^{22} | U^{33} | U^{12} | U^{13} | U^{23} |
Al1 | 0.00333 (13) | 0.00324 (12) | 0.00238 (12) | 0.00001 (15) | 0.000 | 0.000 |
O1 | 0.0033 (3) | 0.0035 (2) | 0.0031 (2) | −0.00084 (19) | 0.000 | 0.000 |
O2 | 0.0037 (3) | 0.0030 (2) | 0.0040 (2) | 0.00001 (19) | 0.000 | 0.000 |
Geometric parameters (Å, º) top
Al1—O1^{i} | 1.8647 (6) | Al1—Al1^{vii} | 2.8315 (7) |
Al1—O1^{ii} | 1.8647 (6) | O1—Al1^{viii} | 1.8647 (6) |
Al1—O1 | 1.8688 (10) | O1—Al1^{ix} | 1.8647 (6) |
Al1—O2^{iii} | 1.9520 (7) | O2—Al1^{x} | 1.9520 (7) |
Al1—O2^{iv} | 1.9520 (7) | O2—Al1^{xi} | 1.9520 (7) |
Al1—O2^{v} | 2.0351 (10) | O2—Al1^{xii} | 2.0351 (10) |
Al1—Al1^{vi} | 2.8315 (7) | | |
| | | |
O1^{i}—Al1—O1^{ii} | 98.79 (4) | O1—Al1—Al1^{vi} | 90.0 |
O1^{i}—Al1—O1 | 94.84 (2) | O2^{iii}—Al1—Al1^{vi} | 136.49 (2) |
O1^{ii}—Al1—O1 | 94.84 (2) | O2^{iv}—Al1—Al1^{vi} | 43.51 (2) |
O1^{i}—Al1—O2^{iii} | 174.41 (4) | O2^{v}—Al1—Al1^{vi} | 90.0 |
O1^{ii}—Al1—O2^{iii} | 83.91 (3) | O1^{i}—Al1—Al1^{vii} | 139.40 (2) |
O1—Al1—O2^{iii} | 89.79 (4) | O1^{ii}—Al1—Al1^{vii} | 40.60 (2) |
O1^{i}—Al1—O2^{iv} | 83.91 (3) | O1—Al1—Al1^{vii} | 90.0 |
O1^{ii}—Al1—O2^{iv} | 174.41 (4) | O2^{iii}—Al1—Al1^{vii} | 43.51 (2) |
O1—Al1—O2^{iv} | 89.79 (4) | O2^{iv}—Al1—Al1^{vii} | 136.49 (2) |
O2^{iii}—Al1—O2^{iv} | 92.98 (4) | O2^{v}—Al1—Al1^{vii} | 90.0 |
O1^{i}—Al1—O2^{v} | 88.05 (4) | Al1^{vi}—Al1—Al1^{vii} | 180.000 (12) |
O1^{ii}—Al1—O2^{v} | 88.05 (4) | Al1^{viii}—O1—Al1^{ix} | 98.79 (4) |
O1—Al1—O2^{v} | 175.56 (4) | Al1^{viii}—O1—Al1 | 127.19 (3) |
O2^{iii}—Al1—O2^{v} | 87.15 (2) | Al1^{ix}—O1—Al1 | 127.19 (3) |
O2^{iv}—Al1—O2^{v} | 87.15 (2) | Al1^{x}—O2—Al1^{xi} | 92.98 (4) |
O1^{i}—Al1—Al1^{vi} | 40.60 (2) | Al1^{x}—O2—Al1^{xii} | 128.81 (3) |
O1^{ii}—Al1—Al1^{vi} | 139.40 (2) | Al1^{xi}—O2—Al1^{xii} | 128.81 (3) |
Symmetry codes: (i) x−1/2, −y+1, −z+1/2; (ii) x−1/2, −y+1, −z−1/2; (iii) x−1/2, −y, −z−1/2; (iv) x−1/2, −y, −z+1/2; (v) x−1, y, z; (vi) x, y, z+1; (vii) x, y, z−1; (viii) x+1/2, −y+1, −z+1/2; (ix) x+1/2, −y+1, −z−1/2; (x) x+1/2, −y, −z−1/2; (xi) x+1/2, −y, −z+1/2; (xii) x+1, y, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H1···O1 | 0.81 (4) | 1.74 (4) | 2.5479 (12) | 179 (6) |