Calcium dipotassium tetra­oxalatozirconate(IV) octa­hydrate

The Ca and Zr atoms in the title compound, poly[octa­aqua­tetra-μ-oxalato-calciumdipotassiumzirconate(IV)], [CaK₂Zr(C₂O₄)₄(H₂O)₈], are chelated by bridging oxalate groups to form a three-dimensional network; the two independent water-coordinated K atoms occupy the space within the network and also inter­act with the oxalate O atoms to result in eight-coordination for the K atoms. The title compound is isostructural with [CdK₂Zr(C₂O₄)₄(H₂O)₈] [Jeanneau, Audebrand & Louer (2002). J. Mater. Chem. 12, 2383–2389]. All the metal ions occupy special positions with site symmetry.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.037
• wR factor = 0.081
• Data-to-parameter ratio = 15.7

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT112_ALERT_2_A ADDSYM Detects Additional (Pseudo) Symm. Elem...          4

Author Response: The space group is I-4 and not I41/a as suggested by checkcif. Editor's comment: this seems to be a glitch; my version of PLATON shows no such problems.

PLAT113_ALERT_2_A ADDSYM Suggests Possible Pseudo/New Spacegroup .      I41/a

Author Response: The reflections that should be absent from the 4~1~ and a-glide symmetry operations are present. In I41/a, the structure refines with non-positive definites to an R exceeding 10%.

PLAT733_ALERT_1_A Torsion Calc  132.07(11), Rep   132.07(1) ......       9.90 su-Ra
              O1  -K1  -O1  -ZR1    3.576   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_A Torsion Calc -132.07(11), Rep  -132.07(1) ......       9.90 su-Ra
              O1  -K1  -O1  -ZR1    4.756   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

Alert level B
PLAT111_ALERT_2_B ADDSYM Detects (Pseudo) Centre of Symmetry .....        100 PerFi
PLAT702_ALERT_1_B Angle   Calc   138.29(9), Rep  138.10(10), Dev..       2.11 Sigma
              O2   -ZR1  -O1      4.755   1.555   3.575
PLAT733_ALERT_1_B Torsion Calc -129.76(11), Rep  -129.76(2) ......       5.50 su-Ra
              O1  -ZR1 -O1  -K1     3.575   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_B Torsion Calc  129.76(11), Rep   129.76(2) ......       5.50 su-Ra
              O1  -ZR1 -O1  -K1     4.755   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_B Torsion Calc -129.39(10), Rep  -129.39(2) ......       5.00 su-Ra
              O4  -CA1 -O4  -K2     8.655   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_B Torsion Calc  129.39(10), Rep   129.39(2) ......       5.00 su-Ra
              O4  -CA1 -O4  -K2     7.465   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_B Torsion Calc -130.59(10), Rep  -130.59(2) ......       5.00 su-Ra
              O4  -K2  -O4  -CA1    7.464   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

PLAT733_ALERT_1_B Torsion Calc  130.59(10), Rep   130.59(2) ......       5.00 su-Ra
              O4  -K2  -O4  -CA1    8.654   1.555   1.555   1.555

Author Response: This is an artifact of three decimal places. The calculated angle is 132.073(11)\% and not 132.07(11)\%A.

Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    O     Ueq(max)/Ueq(min) ...       2.56 Ratio
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C1     -   C2     ...       1.54 Ang.
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4

Alert level G
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           27.43
           From the CIF: _reflns_number_total               1302
           Count of symmetry unique reflns          698
           Completeness (_total/calc)            186.53%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       604
           Fraction of Friedel pairs measured     0.865
           Are heavy atom types Z>Si present        yes
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K

   4 ALERT level A = In general: serious problem
   8 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

  10 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   5 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
   0 ALERT type 5 Informative message, check

---

Computing details

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97.

poly[octaaquatetra-µ-oxalato-calciumdipotassiumzirconium(IV)]

Crystal data

[CaK2Zr(C2O4)4(H2O)8]	Dx = 2.042 Mg m^−3
Mr = 705.71	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4	Cell parameters from 1316 reflections
Hall symbol: I -4	θ = 2.5–24.6°
a = 11.342 (1) Å	µ = 1.18 mm^−1
c = 8.920 (1) Å	T = 293 K
V = 1147.56 (16) Å^3	Block, colorless
Z = 2	0.28 × 0.20 × 0.18 mm
F(000) = 708

Data collection

Bruker APEX CCD diffractometer	1302 independent reflections
Radiation source: fine-focus sealed tube	1199 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.046
ω scans	θmax = 27.4°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→13
Tmin = 0.681, Tmax = 0.816	k = −14→14
6454 measured reflections	l = −11→11

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.037	H-atom parameters constrained
wR(F^2) = 0.081	w = 1/[σ^2(Fo^2) + (0.0434P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
1302 reflections	Δρmax = 0.72 e Å^−3
83 parameters	Δρmin = −0.36 e Å^−3
0 restraints	Absolute structure: Flack (1983), 603 Fridel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.06 (8)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zr1	1.0000	1.0000	0.0000	0.01056 (17)
Ca1	0.5000	1.0000	0.2500	0.0136 (4)
K1	1.0000	1.0000	0.5000	0.0343 (4)
K2	0.5000	1.0000	−0.2500	0.0262 (5)
O1	0.8908 (2)	1.0048 (2)	0.2084 (3)	0.0221 (6)
O2	0.8145 (2)	0.9963 (2)	−0.0618 (3)	0.0234 (6)
O3	0.7077 (2)	1.0040 (2)	0.3035 (3)	0.0255 (7)
O4	0.6264 (2)	0.9891 (2)	0.0179 (4)	0.0264 (7)
O1w	0.7946 (3)	1.1433 (3)	0.5421 (3)	0.055 (1)
O2w	0.6431 (3)	1.2079 (3)	−0.2090 (4)	0.056 (1)
C1	0.7799 (3)	1.0019 (3)	0.1995 (4)	0.0173 (7)
C2	0.7334 (3)	0.9952 (3)	0.0376 (4)	0.0196 (8)
H1w1	0.7353	1.1095	0.5028	0.050*
H1w2	0.7824	1.1529	0.6354	0.050*
H2w1	0.6474	1.2242	−0.1162	0.050*
H2w2	0.6122	1.2654	−0.2557	0.050*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zr1	0.0109 (2)	0.0109 (2)	0.0098 (3)	0.000	0.000	0.000
Ca1	0.0120 (5)	0.0120 (5)	0.0167 (9)	0.000	0.000	0.000
K1	0.0404 (6)	0.0404 (6)	0.0222 (7)	0.000	0.000	0.000
K2	0.0303 (8)	0.0303 (8)	0.018 (1)	0.000	0.000	0.000
O1	0.012 (1)	0.035 (2)	0.019 (1)	−0.001 (1)	0.0002 (1)	−0.001 (1)
O2	0.017 (1)	0.039 (2)	0.015 (1)	0.001 (1)	−0.001 (1)	−0.001 (1)
O3	0.014 (1)	0.044 (2)	0.018 (1)	−0.001 (1)	−0.001 (1)	−0.003 (1)
O4	0.012 (1)	0.045 (2)	0.022 (2)	0.000 (1)	−0.002 (1)	−0.001 (1)
O1w	0.040 (2)	0.083 (3)	0.042 (2)	−0.011 (2)	−0.006 (2)	−0.014 (2)
O2w	0.081 (3)	0.043 (2)	0.045 (2)	0.009 (2)	−0.019 (2)	0.005 (2)
C1	0.016 (2)	0.019 (2)	0.017 (2)	−0.001 (1)	−0.001 (1)	0.002 (2)
C2	0.021 (2)	0.019 (2)	0.019 (2)	−0.001 (2)	−0.001 (1)	−0.003 (1)

Geometric parameters (Å, º)

Zr1—O1	2.234 (2)	K1—O1w^i	2.866 (3)
Zr1—O1^i	2.234 (2)	K1—O1w^vii	2.866 (3)
Zr1—O1^ii	2.234 (2)	K1—O1w^viii	2.866 (3)
Zr1—O1^iii	2.234 (2)	K2—O4	2.789 (3)
Zr1—O2	2.175 (3)	K2—O4^iv	2.789 (3)
Zr1—O2^i	2.175 (3)	K2—O4^ix	2.789 (3)
Zr1—O2^ii	2.175 (3)	K2—O4^x	2.789 (3)
Zr1—O2^iii	2.175 (3)	K2—O2w	2.886 (3)
Ca1—O3	2.404 (2)	K2—O2w^iv	2.886 (3)
Ca1—O3^iv	2.404 (2)	K2—O2w^ix	2.886 (3)
Ca1—O3^v	2.404 (2)	K2—O2w^x	2.886 (3)
Ca1—O3^vi	2.404 (2)	C1—O1	1.260 (4)
Ca1—O4	2.521 (3)	C1—O3	1.239 (4)
Ca1—O4^iv	2.521 (3)	C2—O2	1.277 (4)
Ca1—O4^v	2.521 (3)	C2—O4	1.228 (4)
Ca1—O4^vi	2.521 (3)	C1—C2	1.539 (5)
K1—O1	2.882 (2)	O1w—H1w1	0.85
K1—O1^i	2.882 (2)	O1w—H1w2	0.85
K1—O1^vii	2.882 (2)	O2w—H2w1	0.85
K1—O1^viii	2.882 (2)	O2w—H2w2	0.85
K1—O1w	2.866 (3)
O2—Zr1—O2^ii	93.7 (1)	O1w^vii—K1—O1^vii	76.0 (1)
O2—Zr1—O2^i	150.7 (1)	O1w^viii—K1—O1^vii	118.6 (1)
O2^ii—Zr1—O2^i	93.7 (1)	O1w^i—K1—O1^vii	96.3 (1)
O2—Zr1—O2^iii	93.7 (1)	O1w—K1—O1^vii	69.7 (1)
O2^ii—Zr1—O2^iii	150.7 (1)	O1—K1—O1^vii	144.6 (1)
O2^i—Zr1—O2^iii	93.7 (1)	O1w^vii—K1—O1^i	69.7 (1)
O2—Zr1—O1^ii	79.8 (1)	O1w^viii—K1—O1^i	96.3 (1)
O2^ii—Zr1—O1^ii	71.0 (1)	O1w^i—K1—O1^i	76.0 (1)
O2^i—Zr1—O1^ii	75.8 (1)	O1w—K1—O1^i	118.6 (1)
O2^iii—Zr1—O1^ii	138.1 (1)	O1—K1—O1^i	51.0 (1)
O2—Zr1—O1^iii	75.8 (1)	O1^vii—K1—O1^i	144.6 (1)
O2^ii—Zr1—O1^iii	138.3 (1)	O1w^vii—K1—O1^viii	118.6 (1)
O2^i—Zr1—O1^iii	79.8 (1)	O1w^viii—K1—O1^viii	76.0 (1)
O2^iii—Zr1—O1^iii	71.0 (1)	O1w^i—K1—O1^viii	69.7 (1)
O1^ii—Zr1—O1^iii	67.4 (1)	O1w—K1—O1^viii	96.3 (1)
O2—Zr1—O1^i	138.3 (1)	O1—K1—O1^viii	144.6 (1)
O2^ii—Zr1—O1^i	79.8 (1)	O1^vii—K1—O1^viii	51 (1)
O2^i—Zr1—O1^i	71.0 (1)	O1^i—K1—O1^viii	144.6 (1)
O2^iii—Zr1—O1^i	75.8 (1)	O4^ix—K2—O4	137.2 (1)
O1^ii—Zr1—O1^i	133.8 (1)	O4^ix—K2—O4^iv	137.2 (1)
O1^iii—Zr1—O1^i	133.8 (1)	O4—K2—O4^iv	62.1 (1)
O2—Zr1—O1	71.0 (1)	O4^ix—K2—O4^x	62.1 (1)
O2^ii—Zr1—O1	75.8 (1)	O4—K2—O4^x	137.2 (1)
O2^i—Zr1—O1	138.3 (1)	O4^iv—K2—O4^x	137.2 (1)
O2^iii—Zr1—O1	79.8 (1)	O4^ix—K2—O2w	123.6 (1)
O1^ii—Zr1—O1	133.8 (1)	O4—K2—O2w	68.8 (1)
O1^iii—Zr1—O1	133.8 (1)	O4^iv—K2—O2w	98.3 (1)
O1^i—Zr1—O1	67.4 (1)	O4^x—K2—O2w	70.4 (1)
O3^vi—Ca1—O3	92.3 (1)	O4^ix—K2—O2w^iv	70.4 (1)
O3^vi—Ca1—O3^iv	92.3 (1)	O4—K2—O2w^iv	98.3 (1)
O3—Ca1—O3^iv	157.1 (1)	O4^iv—K2—O2w^iv	68.8 (1)
O3^vi—Ca1—O3^v	157.1 (1)	O4^x—K2—O2w^iv	123.6 (1)
O3—Ca1—O3^v	92.3 (1)	O2w—K2—O2w^iv	165.42 (2)
O3^iv—Ca1—O3^v	92.3 (1)	O4^ix—K2—O2w^x	98.3 (1)
O3^vi—Ca1—O4^vi	66.9 (1)	O4—K2—O2w^x	123.6 (1)
O3—Ca1—O4^vi	77.2 (1)	O4^iv—K2—O2w^x	70.4 (1)
O3^iv—Ca1—O4^vi	84.0 (1)	O4^x—K2—O2w^x	68.8 (1)
O3^v—Ca1—O4^vi	136.0 (1)	O2w—K2—O2w^x	90.9 (1)
O3^vi—Ca1—O4^iv	77.2 (1)	O2w^iv—K2—O2w^x	90.9 (1)
O3—Ca1—O4^iv	136.0 (1)	O4^ix—K2—O2w^ix	68.8 (1)
O3^iv—Ca1—O4^iv	66.9 (1)	O4—K2—O2w^ix	70.4 (1)
O3^v—Ca1—O4^iv	84.0 (1)	O4^iv—K2—O2w^ix	123.6 (1)
O4^vi—Ca1—O4^iv	132.4 (1)	O4^x—K2—O2w^ix	98.3 (1)
O3^vi—Ca1—O4	84.0 (1)	O2w—K2—O2w^ix	90.9 (1)
O3—Ca1—O4	66.9 (1)	O2w^iv—K2—O2w^ix	90.9 (1)
O3^iv—Ca1—O4	136.0 (1)	O2w^x—K2—O2w^ix	165.4 (2)
O3^v—Ca1—O4	77.2 (1)	C1—O1—Zr1	120.0 (2)
O4^vi—Ca1—O4	132.4 (1)	C1—O1—K1	119.0 (2)
O4^iv—Ca1—O4	69.6 (1)	Zr1—O1—K1	120.8 (1)
O3^vi—Ca1—O4^v	136.0 (1)	C2—O2—Zr1	121.4 (2)
O3—Ca1—O4^v	84.0 (1)	C1—O3—Ca1	119.9 (2)
O3^iv—Ca1—O4^v	77.2 (1)	C2—O4—Ca1	116.2 (3)
O3^v—Ca1—O4^v	66.9 (1)	C2—O4—K2	128.9 (3)
O4^vi—Ca1—O4^v	69.6 (1)	Ca1—O4—K2	114.2 (1)
O4^iv—Ca1—O4^v	132.4 (1)	O3—C1—O1	127.8 (3)
O4—Ca1—O4^v	132.4 (1)	O3—C1—C2	118.5 (3)
O1w^vii—K1—O1w^viii	164.9 (1)	O1—C1—C2	113.7 (3)
O1w^vii—K1—O1w^i	91.0 (1)	O4—C2—O2	127.8 (3)
O1w^viii—K1—O1w^i	91.0 (1)	O4—C2—C1	118.4 (3)
O1w^vii—K1—O1w	91.0 (1)	O2—C2—C1	113.8 (3)
O1w^viii—K1—O1w	91.0 (1)	K1—O1w—H1w1	109.5
O1w^i—K1—O1w	164.9 (1)	K1—O1w—H1w2	109.5
O1w^vii—K1—O1	96.3 (1)	H1w1—O1w—H1w2	109.5
O1w^viii—K1—O1	69.7 (1)	K2—O2w—H2w1	109.5
O1w^i—K1—O1	118.6 (1)	K2—O2w—H2w2	109.5
O1w—K1—O1	76.0 (1)	H2w1—O2w—H2w2	109.5
O2—Zr1—O1—C1	0.9 (2)	O3^iv—Ca1—O4—C2	179.5 (2)
O2^ii—Zr1—O1—C1	99.9 (3)	O3^v—Ca1—O4—C2	−100.7 (3)
O2^i—Zr1—O1—C1	179.3 (2)	O4^vi—Ca1—O4—C2	41.6 (3)
O2^iii—Zr1—O1—C1	−96.6 (3)	O4^iv—Ca1—O4—C2	171.0 (3)
O1^ii—Zr1—O1—C1	54.9 (3)	O4^v—Ca1—O4—C2	−59.6 (3)
O1^iii—Zr1—O1—C1	−45.6 (3)	O3^vi—Ca1—O4—K2	−78.5 (1)
O1^i—Zr1—O1—C1	−175.4 (3)	O3—Ca1—O4—K2	−173.6 (1)
O2—Zr1—O1—K1	176.2 (1)	O3^iv—Ca1—O4—K2	8.5 (2)
O2^ii—Zr1—O1—K1	−84.7 (1)	O3^v—Ca1—O4—K2	88.3 (1)
O2^i—Zr1—O1—K1	−5.3 (2)	O4^vi—Ca1—O4—K2	−129.39 (2)
O2^iii—Zr1—O1—K1	78.7 (1)	O4^v—Ca1—O4—K2	129.39 (2)
O1^ii—Zr1—O1—K1	−129.76 (2)	O4^ix—K2—O4—C2	59.8 (4)
O1^iii—Zr1—O1—K1	129.76 (2)	O4^iv—K2—O4—C2	−169.6 (3)
O1w^vii—K1—O1—C1	−127.2 (2)	O4^x—K2—O4—C2	−39.0 (3)
O1w^viii—K1—O1—C1	58.6 (2)	O2w—K2—O4—C2	−57.2 (3)
O1w^i—K1—O1—C1	138.2 (2)	O2w^iv—K2—O4—C2	129.8 (3)
O1w—K1—O1—C1	−37.8 (2)	O2w^x—K2—O4—C2	−133.5 (3)
O1^vii—K1—O1—C1	−52.5 (3)	O2w^ix—K2—O4—C2	41.8 (3)
O1^i—K1—O1—C1	175.4 (3)	Ca1^xi—K2—O4—C2	10.4 (3)
O1^viii—K1—O1—C1	43.3 (3)	Ca1—K2—O4—C2	−169.6 (3)
O1w^vii—K1—O1—Zr1	57.4 (1)	O4^ix—K2—O4—Ca1	−130.59 (2)
O1w^viii—K1—O1—Zr1	−116.8 (1)	O4^x—K2—O4—Ca1	130.59 (2)
O1w^i—K1—O1—Zr1	−37.2 (2)	O2w—K2—O4—Ca1	112.4 (1)
O1w—K1—O1—Zr1	146.8 (1)	O2w^iv—K2—O4—Ca1	−60.6 (1)
O1^vii—K1—O1—Zr1	132.07 (1)	O2w^x—K2—O4—Ca1	36.1 (2)
O1^viii—K1—O1—Zr1	−132.07 (1)	O2w^ix—K2—O4—Ca1	−148.6 (1)
O2^ii—Zr1—O2—C2	−75.5 (3)	Ca1—O3—C1—O1	179.1 (3)
O2^i—Zr1—O2—C2	−179.7 (3)	Ca1—O3—C1—C2	−0.7 (4)
O2^iii—Zr1—O2—C2	76.1 (3)	Zr1—O1—C1—O3	−179.9 (3)
O1^ii—Zr1—O2—C2	−145.5 (3)	K1—O1—C1—O3	4.6 (5)
O1^iii—Zr1—O2—C2	145.5 (3)	Zr1—O1—C1—C2	0.0 (4)
O1^i—Zr1—O2—C2	3.4 (4)	K1—O1—C1—C2	−175.5 (2)
O1—Zr1—O2—C2	−1.8 (3)	Ca1—O4—C2—O2	−177.1 (3)
O3^vi—Ca1—O3—C1	−80.9 (3)	K2—O4—C2—O2	−7.7 (5)
O3^iv—Ca1—O3—C1	177.9 (3)	Ca1—O4—C2—C1	3.2 (4)
O3^v—Ca1—O3—C1	76.6 (3)	K2—O4—C2—C1	172.6 (2)
O4^vi—Ca1—O3—C1	−146.5 (3)	Zr1—O2—C2—O4	−177.3 (3)
O4^iv—Ca1—O3—C1	−7.1 (3)	Zr1—O2—C2—C1	2.4 (4)
O4—Ca1—O3—C1	1.6 (3)	O3—C1—C2—O4	−1.8 (5)
O4^v—Ca1—O3—C1	143.1 (3)	O1—C1—C2—O4	178.3 (3)
O3^vi—Ca1—O4—C2	92.5 (3)	O3—C1—C2—O2	178.4 (3)
O3—Ca1—O4—C2	−2.6 (2)	O1—C1—C2—O2	−1.5 (5)

Symmetry codes: (i) −x+2, −y+2, z; (ii) y, −x+2, −z; (iii) −y+2, x, −z; (iv) −x+1, −y+2, z; (v) y−1/2, −x+3/2, −z+1/2; (vi) −y+3/2, x+1/2, −z+1/2; (vii) y, −x+2, −z+1; (viii) −y+2, x, −z+1; (ix) y−1/2, −x+3/2, −z−1/2; (x) −y+3/2, x+1/2, −z−1/2; (xi) x, y, z−1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1w—H1w1···O3	0.85	2.16	2.828 (4)	135
O1w—H1w2···O2w^xii	0.85	2.19	2.901 (5)	141
O2w—H2w1···O1w^xiii	0.85	2.16	2.893 (5)	144
O2w—H2w2···O2^x	0.85	2.12	2.854 (4)	145

Symmetry codes: (x) −y+3/2, x+1/2, −z−1/2; (xii) x, y, z+1; (xiii) −x+3/2, −y+5/2, z−1/2.