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Hexaaqua­magnesium(II) sulfate penta­hydrate, [Mg(H2O)6]SO4·5H2O, and hexa­aqua­magnesium(II) chromate(II) penta­hydrate, [Mg(H2O)6][CrO4]·5H2O, are isomorphous, being composed of hexa­aqua­magnesium(II) octa­hedra, [Mg(H2O)6]2+, and sulfate (chromate) tetra­hedral oxyanions, SO42− (CrO42−), linked by hydrogen bonds. There are two symmetry-inequivalent centrosymmetric octa­hedra: M1 at (0, 0, 0) donates hydrogen bonds directly to the tetra­hedral oxyanion, T1, at (0.405, 0.320, 0.201), whereas the M2 octa­hedron at (0, 0, {1 \over 2}) is linked to the oxyanion via five inter­stitial water mol­ecules. Substitution of CrVI for SVI leads to a substantial expansion of T1, since the Cr—O bond is approximately 12% longer than the S—O bond. This expansion is propagated through the hydrogen-bonded framework to produce a 3.3% increase in unit-cell volume; the greatest part of this chemically induced strain is manifested along the b* direction. The hydrogen bonds in the chromate compound mitigate ∼20% of the expected strain due to the larger oxyanion, becoming shorter (i.e. stronger) and more linear than in the sulfate analogue. The bifurcated hydrogen bond donated by one of the inter­stitial water mol­ecules is significantly more symmetrical in the chromate analogue.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270113005751/ku3086sup1.cif
Contains datablocks I, II, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270113005751/ku3086Isup2.hkl
Contains datablock I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270113005751/ku3086IIsup3.hkl
Contains datablock II

Computing details top

For both compounds, data collection: SXD2001 (Gutmann, 2005); cell refinement: SXD2001 (Gutmann, 2005); data reduction: SXD2001 (Gutmann, 2005); program(s) used to solve structure: n/a; program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

(I) Hexaaquamagnesium(II) sulfate pentahydrate top
Crystal data top
[Mg(H2O)6](SO4)·5H2OZ = 2
Mr = 318.53F(000) = 26
Triclinic, P1Dx = 1.508 Mg m3
a = 6.7283 (13) ÅMelting point: 275 K
b = 6.7839 (14) ÅNeutron radiation, λ = 0.48-7.0 Å
c = 17.332 (4) ÅCell parameters from 550 reflections
α = 88.181 (13)°µ = 0.0 mm1
β = 89.349 (14)°T = 5 K
γ = 62.515 (12)°Cuboid, colourless
V = 701.5 (2) Å32.00 × 2.00 × 2.00 mm
Data collection top
SXD beamline
diffractometer
Rint = 0.000
Radiation source: ISIS neutron spallation sourceθmax = 84.9°, θmin = 9.0°
time–of–flight Laue diffraction scansh = 1716
14936 measured reflectionsk = 1816
14936 independent reflectionsl = 3725
14936 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.067All H-atom parameters refined
wR(F2) = 0.187 w = 1/[σ2(Fo2) + (0.1001P)2 + 16.5668P]
where P = (Fo2 + 2Fc2)/3
S = 1.11(Δ/σ)max = 0.001
14936 reflectionsΔρmax = 1.97 e Å3
367 parametersΔρmin = 2.09 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0187 (4)
Special details top

Experimental. For peak integration a local UB matrix refined for each frame, using approximately 50 reflections from each of the 11 detectors. Hence _cell_measurement_reflns_used 550 For final cell dimensions a weighted average of all local cells was calculated. Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.48–7.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7–2.5 Angstroms. The data-collection procedures on the SXD instrument used for the single-crystal neutron data collection are most recently summarized in the Appendix to the following paper: Wilson, C.C. (1997). J. Mol. Struct. 405, 207–217

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. The variable wavelength nature of the data collection procedure means that sensible values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given. Instead, the following limits are given: _diffrn_reflns_sin(theta)/lambda_min 0.06 _diffrn_reflns_sin(theta)/lambda_max 1.38 _refine_diff_density_max/min is given in Fermi per per angstrom cubed not electrons per angstrom cubed. Another way to consider the _refine_diff_density_ is as a percentage of the scattering density of a given atom: _refine_diff_density_max = 4% of oxygen _refine_diff_density_min = -4% of oxygen 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
xyzUiso*/Ueq
Mg11.00000.00000.00000.00309 (17)
OW10.65691 (14)0.17344 (16)0.00821 (6)0.00641 (14)
H1A0.5556 (4)0.2338 (5)0.05090 (16)0.0226 (5)
H1B0.5648 (4)0.1897 (4)0.03695 (15)0.0195 (4)
OW20.99062 (15)0.26902 (14)0.05542 (7)0.00605 (14)
H2A1.1165 (4)0.4050 (4)0.07339 (18)0.0214 (4)
H2B0.8563 (3)0.2707 (4)0.07618 (16)0.0187 (4)
OW31.04714 (15)0.11065 (15)0.10544 (6)0.00586 (14)
H3A1.0430 (5)0.0428 (4)0.15481 (15)0.0210 (4)
H3B1.1320 (4)0.1928 (4)0.11117 (16)0.0209 (4)
Mg21.00000.00000.50000.00292 (17)
OW41.15158 (14)0.11150 (15)0.39413 (6)0.00532 (13)
H4A1.3000 (3)0.1225 (4)0.38388 (15)0.0181 (4)
H4B1.0784 (4)0.0869 (4)0.34364 (15)0.0182 (4)
OW50.80442 (16)0.15462 (16)0.48629 (7)0.00664 (14)
H5A0.7715 (4)0.2430 (4)0.52506 (16)0.0200 (4)
H5B0.7129 (4)0.1394 (4)0.44090 (16)0.0195 (4)
OW60.75619 (14)0.28506 (15)0.44646 (6)0.00600 (14)
H6A0.7997 (4)0.3342 (4)0.39855 (16)0.0192 (4)
H6B0.6015 (3)0.3155 (4)0.43816 (17)0.0197 (4)
S10.4053 (2)0.3200 (3)0.20064 (11)0.0020 (2)
O10.31690 (14)0.33018 (14)0.12243 (6)0.00443 (13)
O20.21813 (14)0.43819 (14)0.25486 (6)0.00484 (13)
O30.53006 (14)0.08315 (14)0.22698 (6)0.00493 (13)
O40.55692 (14)0.42090 (15)0.20021 (6)0.00561 (14)
OW70.31115 (15)0.40412 (15)0.41252 (6)0.00597 (14)
H7A0.2872 (4)0.4092 (4)0.35678 (15)0.0202 (4)
H7B0.2379 (4)0.5584 (4)0.42643 (19)0.0246 (5)
OW80.60549 (15)0.24763 (15)0.11976 (6)0.00598 (14)
H8A0.5589 (4)0.1284 (4)0.15631 (16)0.0201 (4)
H8B0.5906 (4)0.3698 (4)0.14565 (17)0.0205 (4)
OW90.56102 (15)0.14706 (15)0.36038 (6)0.00562 (13)
H9A0.5357 (4)0.0430 (4)0.31630 (16)0.0192 (4)
H9B0.6588 (4)0.2941 (3)0.33980 (16)0.0185 (4)
OW100.83217 (15)0.43812 (16)0.30797 (6)0.00604 (14)
H10A0.7453 (4)0.4115 (4)0.26813 (16)0.0195 (4)
H10B0.9726 (4)0.4156 (4)0.28472 (16)0.0204 (4)
OW110.99540 (15)0.09053 (15)0.24597 (7)0.00620 (14)
H11A1.0629 (4)0.2510 (3)0.24017 (17)0.0206 (4)
H11B0.8344 (3)0.0324 (4)0.23867 (16)0.0194 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Mg10.0020 (3)0.0035 (3)0.0033 (5)0.0009 (3)0.0001 (3)0.0002 (3)
OW10.0027 (2)0.0092 (3)0.0057 (4)0.0014 (2)0.0003 (2)0.0013 (3)
H1A0.0161 (8)0.0311 (11)0.0151 (11)0.0058 (7)0.0073 (7)0.0080 (9)
H1B0.0150 (7)0.0279 (10)0.0139 (10)0.0082 (7)0.0035 (6)0.0019 (8)
OW20.0045 (2)0.0048 (3)0.0082 (4)0.0018 (2)0.0005 (2)0.0018 (3)
H2A0.0144 (7)0.0152 (7)0.0271 (13)0.0008 (6)0.0029 (7)0.0061 (8)
H2B0.0129 (7)0.0216 (8)0.0232 (11)0.0095 (6)0.0032 (7)0.0017 (8)
OW30.0066 (3)0.0083 (3)0.0041 (4)0.0047 (2)0.0004 (2)0.0009 (3)
H3A0.0291 (10)0.0277 (10)0.0111 (10)0.0177 (9)0.0008 (8)0.0050 (8)
H3B0.0261 (10)0.0261 (9)0.0195 (12)0.0198 (8)0.0014 (8)0.0010 (9)
Mg20.0026 (3)0.0031 (3)0.0031 (5)0.0014 (3)0.0000 (3)0.0003 (3)
OW40.0041 (2)0.0078 (3)0.0037 (4)0.0023 (2)0.0006 (2)0.0010 (3)
H4A0.0119 (6)0.0245 (9)0.0190 (11)0.0094 (6)0.0026 (6)0.0019 (8)
H4B0.0175 (7)0.0245 (9)0.0118 (10)0.0090 (7)0.0040 (6)0.0003 (8)
OW50.0078 (3)0.0094 (3)0.0055 (4)0.0064 (2)0.0016 (3)0.0015 (3)
H5A0.0257 (9)0.0248 (9)0.0159 (11)0.0174 (8)0.0001 (8)0.0056 (8)
H5B0.0201 (8)0.0251 (9)0.0159 (11)0.0127 (7)0.0071 (7)0.0012 (8)
OW60.0038 (2)0.0062 (3)0.0063 (4)0.0010 (2)0.0003 (2)0.0016 (3)
H6A0.0178 (8)0.0230 (9)0.0160 (11)0.0094 (7)0.0015 (7)0.0062 (7)
H6B0.0101 (6)0.0251 (9)0.0232 (12)0.0077 (6)0.0013 (6)0.0018 (8)
S10.0013 (4)0.0026 (4)0.0020 (7)0.0009 (3)0.0003 (4)0.0004 (4)
O10.0042 (2)0.0060 (3)0.0030 (4)0.0022 (2)0.0009 (2)0.0006 (2)
O20.0032 (2)0.0056 (3)0.0045 (4)0.0008 (2)0.0019 (2)0.0017 (3)
O30.0047 (2)0.0032 (2)0.0056 (4)0.0007 (2)0.0003 (2)0.0007 (2)
O40.0052 (3)0.0076 (3)0.0065 (4)0.0052 (2)0.0005 (2)0.0004 (3)
OW70.0059 (3)0.0057 (3)0.0061 (4)0.0025 (2)0.0002 (2)0.0001 (3)
H7A0.0231 (9)0.0258 (9)0.0101 (10)0.0100 (8)0.0006 (7)0.0000 (8)
H7B0.0251 (10)0.0139 (7)0.0304 (15)0.0050 (7)0.0027 (9)0.0081 (9)
OW80.0059 (3)0.0068 (3)0.0058 (4)0.0034 (2)0.0001 (2)0.0002 (3)
H8A0.0235 (9)0.0174 (7)0.0194 (11)0.0090 (7)0.0047 (8)0.0077 (8)
H8B0.0266 (10)0.0175 (8)0.0215 (12)0.0139 (7)0.0011 (8)0.0034 (8)
OW90.0052 (3)0.0072 (3)0.0044 (4)0.0028 (2)0.0003 (2)0.0002 (3)
H9A0.0214 (8)0.0179 (8)0.0168 (11)0.0080 (7)0.0004 (7)0.0056 (7)
H9B0.0181 (7)0.0137 (7)0.0200 (11)0.0040 (6)0.0023 (7)0.0036 (7)
OW100.0055 (3)0.0082 (3)0.0052 (4)0.0038 (2)0.0003 (2)0.0004 (3)
H10A0.0199 (8)0.0260 (9)0.0164 (11)0.0136 (7)0.0035 (7)0.0022 (8)
H10B0.0128 (7)0.0266 (9)0.0223 (12)0.0095 (7)0.0057 (7)0.0034 (9)
OW110.0053 (3)0.0065 (3)0.0061 (4)0.0021 (2)0.0003 (2)0.0001 (3)
H11A0.0206 (8)0.0120 (6)0.0256 (13)0.0043 (6)0.0013 (8)0.0044 (8)
H11B0.0106 (6)0.0215 (8)0.0228 (12)0.0047 (6)0.0010 (6)0.0002 (8)
Geometric parameters (Å, º) top
Mg1—OW12.0566 (9)OW4—H4B0.980 (3)
Mg1—OW1i2.0566 (9)OW5—H5A0.977 (3)
Mg1—OW22.0617 (11)OW5—H5B0.978 (3)
Mg1—OW2i2.0618 (10)OW6—H6A0.976 (3)
Mg1—OW32.0794 (10)OW6—H6B0.975 (2)
Mg1—OW3i2.0794 (10)S1—O41.4673 (17)
OW1—H1A0.964 (2)S1—O11.473 (2)
OW1—H1B0.975 (3)S1—O21.4836 (17)
OW2—H2A0.965 (2)S1—O31.4875 (19)
OW2—H2B0.974 (2)OW7—H7A0.978 (3)
OW3—H3A0.965 (3)OW7—H7B0.966 (2)
OW3—H3B0.972 (2)OW8—H8A0.973 (2)
Mg2—OW52.0458 (9)OW8—H8B0.975 (3)
Mg2—OW5ii2.0458 (9)OW9—H9A0.984 (3)
Mg2—OW62.0699 (11)OW9—H9B0.983 (2)
Mg2—OW6ii2.0699 (11)OW10—H10A0.983 (2)
Mg2—OW4ii2.0767 (10)OW10—H10B0.970 (2)
Mg2—OW42.0767 (10)OW11—H11A0.975 (2)
OW4—H4A0.981 (2)OW11—H11B0.975 (2)
OW1—Mg1—OW1i180.0OW5—Mg2—OW4ii89.25 (4)
OW1—Mg1—OW289.36 (4)OW5ii—Mg2—OW4ii90.75 (4)
OW1i—Mg1—OW290.64 (4)OW6—Mg2—OW4ii89.77 (4)
OW1—Mg1—OW2i90.64 (4)OW6ii—Mg2—OW4ii90.23 (4)
OW1i—Mg1—OW2i89.36 (4)OW5—Mg2—OW490.75 (4)
OW2—Mg1—OW2i180.0OW5ii—Mg2—OW489.25 (4)
OW1—Mg1—OW392.58 (4)OW6—Mg2—OW490.23 (4)
OW1i—Mg1—OW387.42 (4)OW6ii—Mg2—OW489.77 (4)
OW2—Mg1—OW390.06 (4)OW4ii—Mg2—OW4180.0
OW2i—Mg1—OW389.94 (4)Mg2—OW4—H4A119.50 (16)
OW1—Mg1—OW3i87.42 (4)Mg2—OW4—H4B127.50 (15)
OW1i—Mg1—OW3i92.58 (4)H4A—OW4—H4B105.8 (2)
OW2—Mg1—OW3i89.94 (4)Mg2—OW5—H5A127.10 (17)
OW2i—Mg1—OW3i90.06 (4)Mg2—OW5—H5B125.54 (18)
OW3—Mg1—OW3i179.999 (2)H5A—OW5—H5B107.0 (2)
Mg1—OW1—H1A133.41 (19)Mg2—OW6—H6A116.31 (15)
Mg1—OW1—H1B119.44 (15)Mg2—OW6—H6B124.88 (18)
H1A—OW1—H1B106.7 (2)H6A—OW6—H6B105.0 (2)
Mg1—OW2—H2A127.25 (17)O4—S1—O1110.31 (13)
Mg1—OW2—H2B125.06 (16)O4—S1—O2109.66 (10)
H2A—OW2—H2B106.9 (2)O1—S1—O2110.04 (11)
Mg1—OW3—H3A124.24 (15)O4—S1—O3109.34 (11)
Mg1—OW3—H3B123.21 (19)O1—S1—O3108.82 (10)
H3A—OW3—H3B108.4 (2)O2—S1—O3108.64 (13)
OW5—Mg2—OW5ii179.998 (1)H7A—OW7—H7B104.1 (3)
OW5—Mg2—OW689.93 (4)H8A—OW8—H8B107.1 (2)
OW5ii—Mg2—OW690.07 (4)H9A—OW9—H9B104.3 (2)
OW5—Mg2—OW6ii90.07 (4)H10A—OW10—H10B107.3 (2)
OW5ii—Mg2—OW6ii89.93 (4)H11A—OW11—H11B107.0 (2)
OW6—Mg2—OW6ii180.0
Symmetry codes: (i) x+2, y, z; (ii) x+2, y, z+1.
(II) Hexaaquamagnesium(II) chromate pentahydrate top
Crystal data top
[Mg(H2O)6](CrO4)·H2OV = 724.8 (4) Å3
Mr = 338.46Z = 2
Triclinic, P1F(000) = 28
a = 6.7721 (18) ÅDx = 1.551 Mg m3
b = 6.917 (2) ÅNeutron radiation, λ = 0.48-7.0 Å
c = 17.410 (5) ÅCell parameters from 330 reflections
α = 88.21 (2)°T = 10 K
β = 89.43 (2)°Cuboid, yellow
γ = 62.768 (18)°2.00 × 2.00 × 2.00 mm
Data collection top
SXD beamline
diffractometer
8624 independent reflections
Radiation source: ISIS neutron spallation source8624 reflections with I > 2σ(I)
Detector resolution: 0 pixels mm-1Rint = 0.000
time–of–flight Laue diffraction scansθmax = 88.4°, θmin = 8.0°
Absorption correction: numerical
The linear absorption coefficient is wavelength-dependent and is calculated as: µ = 4.595 + 0.015 λ [cm-1], as determined by Gaussian integration in SXD2001 (Gutmann, 2005)
h = 1516
k = 1513
8624 measured reflectionsl = 4640
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.083All H-atom parameters refined
wR(F2) = 0.224 w = 1/[σ2(Fo2) + (0.1187P)2 + 33.4697P]
where P = (Fo2 + 2Fc2)/3
S = 1.11(Δ/σ)max < 0.001
8624 reflectionsΔρmax = 1.88 e Å3
369 parametersΔρmin = 1.66 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0079 (3)
Special details top

Experimental. For peak integration a local UB matrix refined for each frame, using approximately 30 reflections from each of the 11 detectors. Hence _cell_measurement_reflns_used 330 For final cell dimensions a weighted average of all local cells was calculated. Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.48–7.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7–2.5 Angstroms. The data-collection procedures on the SXD instrument used for the single-crystal neutron data collection are most recently summarized in the Appendix to the following paper: Wilson, C.C. (1997). J. Mol. Struct. 405, 207–217

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. The variable wavelength nature of the data-collection procedure means that sensible values of _diffrn_reflns_theta_min and _diffrn_reflns_theta_max cannot be given. Instead, the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.08 _diffrn_reflns_sin(theta)/lambda_max 1.38 _refine_diff_density_max/min is given in Fermi per per angstrom cubed not electrons per angstrom cubed. Another way to consider the _refine_diff_density_ is as a percentage of the scattering density of a given atom: _refine_diff_density_max = 3% of oxygen _refine_diff_density_min = -3% of oxygen 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
xyzUiso*/Ueq
Mg11.00000.00000.00000.0031 (5)
OW10.6591 (3)0.1751 (4)0.00642 (11)0.0070 (4)
H1A0.5558 (7)0.2382 (10)0.0478 (3)0.0242 (11)
H1B0.5686 (7)0.1860 (9)0.0386 (3)0.0206 (9)
OW20.9837 (3)0.2640 (4)0.05091 (11)0.0062 (4)
H2A1.1062 (7)0.4002 (9)0.0673 (3)0.0228 (10)
H2B0.8512 (7)0.2622 (9)0.0740 (3)0.0202 (9)
OW31.0464 (3)0.1017 (4)0.10562 (11)0.0067 (4)
H3A1.0425 (8)0.0365 (9)0.1555 (2)0.0216 (9)
H3B1.1223 (8)0.1903 (10)0.1096 (3)0.0232 (10)
Mg21.00000.00000.50000.0040 (5)
OW41.1484 (3)0.1033 (4)0.39480 (11)0.0062 (4)
H4A1.2979 (6)0.1184 (9)0.3850 (3)0.0189 (9)
H4B1.0780 (7)0.0798 (9)0.3443 (2)0.0197 (9)
OW50.8066 (3)0.1528 (4)0.48574 (11)0.0069 (4)
H5A0.7719 (8)0.2393 (9)0.5234 (3)0.0209 (9)
H5B0.7144 (7)0.1370 (9)0.4409 (2)0.0189 (9)
OW60.7564 (3)0.2810 (4)0.44853 (11)0.0056 (4)
H6A0.7983 (7)0.3341 (9)0.4012 (3)0.0208 (9)
H6B0.6015 (6)0.3156 (9)0.4411 (3)0.0208 (10)
Cr10.4078 (4)0.3200 (6)0.20166 (15)0.0022 (5)
O10.3001 (3)0.3376 (4)0.11601 (10)0.0051 (3)
O20.2081 (3)0.4569 (4)0.26429 (11)0.0060 (3)
O30.5424 (3)0.0602 (4)0.22978 (11)0.0059 (4)
O40.5838 (3)0.4215 (4)0.19749 (11)0.0062 (4)
OW70.3116 (3)0.4086 (4)0.41912 (11)0.0062 (4)
H7A0.2786 (7)0.4262 (10)0.3644 (2)0.0221 (10)
H7B0.2406 (9)0.5530 (10)0.4380 (4)0.0276 (11)
OW80.6070 (3)0.2410 (4)0.11869 (12)0.0069 (4)
H8A0.5670 (8)0.1290 (9)0.1576 (3)0.0207 (8)
H8B0.6039 (8)0.3656 (9)0.1452 (3)0.0210 (9)
OW90.5608 (3)0.1510 (4)0.36308 (11)0.0064 (4)
H9A0.5411 (7)0.0546 (9)0.3179 (2)0.0204 (9)
H9B0.6573 (7)0.2973 (8)0.3446 (3)0.0196 (9)
OW100.8338 (3)0.4416 (4)0.31354 (11)0.0070 (4)
H10A0.7579 (7)0.4168 (10)0.2706 (3)0.0213 (9)
H10B0.9740 (6)0.4303 (9)0.2930 (3)0.0210 (9)
OW110.9964 (3)0.0875 (4)0.24672 (11)0.0061 (4)
H11A1.0639 (8)0.2447 (9)0.2448 (3)0.0225 (9)
H11B0.8371 (6)0.0362 (9)0.2411 (3)0.0224 (10)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Mg10.0024 (8)0.0037 (13)0.0036 (9)0.0018 (8)0.0000 (7)0.0003 (9)
OW10.0038 (5)0.0096 (10)0.0058 (7)0.0016 (6)0.0005 (5)0.0002 (7)
H1A0.0193 (17)0.030 (3)0.0160 (17)0.0044 (18)0.0077 (13)0.0074 (17)
H1B0.0166 (15)0.027 (3)0.0164 (16)0.0083 (16)0.0042 (13)0.0008 (16)
OW20.0055 (6)0.0056 (9)0.0082 (7)0.0033 (6)0.0010 (5)0.0026 (7)
H2A0.0158 (15)0.016 (2)0.030 (2)0.0019 (16)0.0044 (15)0.0075 (19)
H2B0.0152 (14)0.022 (2)0.0236 (19)0.0084 (16)0.0052 (13)0.0009 (17)
OW30.0073 (6)0.0089 (10)0.0053 (7)0.0050 (7)0.0003 (5)0.0002 (7)
H3A0.030 (2)0.026 (3)0.0123 (15)0.016 (2)0.0019 (14)0.0045 (16)
H3B0.029 (2)0.025 (3)0.026 (2)0.021 (2)0.0023 (17)0.0004 (19)
Mg20.0034 (8)0.0053 (13)0.0029 (9)0.0016 (9)0.0001 (7)0.0002 (9)
OW40.0043 (6)0.0087 (10)0.0052 (6)0.0027 (6)0.0009 (5)0.0010 (6)
H4A0.0133 (13)0.025 (2)0.0208 (17)0.0109 (16)0.0021 (12)0.0002 (17)
H4B0.0197 (15)0.027 (3)0.0138 (15)0.0120 (17)0.0054 (13)0.0008 (16)
OW50.0092 (7)0.0098 (10)0.0054 (6)0.0077 (7)0.0014 (5)0.0008 (7)
H5A0.0269 (18)0.027 (3)0.0179 (17)0.0203 (19)0.0013 (14)0.0037 (17)
H5B0.0204 (16)0.024 (2)0.0158 (16)0.0128 (17)0.0057 (13)0.0018 (16)
OW60.0053 (6)0.0045 (9)0.0064 (7)0.0016 (6)0.0003 (5)0.0018 (6)
H6A0.0191 (15)0.025 (2)0.0179 (16)0.0105 (17)0.0018 (13)0.0084 (17)
H6B0.0109 (13)0.027 (3)0.0235 (19)0.0081 (16)0.0021 (13)0.0017 (18)
Cr10.0033 (8)0.0025 (13)0.0019 (9)0.0023 (9)0.0007 (7)0.0006 (9)
O10.0045 (6)0.0077 (10)0.0025 (6)0.0023 (6)0.0009 (5)0.0004 (6)
O20.0044 (6)0.0060 (9)0.0055 (6)0.0006 (6)0.0017 (5)0.0015 (6)
O30.0050 (6)0.0048 (9)0.0057 (7)0.0004 (6)0.0003 (5)0.0018 (6)
O40.0056 (6)0.0082 (10)0.0067 (7)0.0049 (7)0.0005 (5)0.0007 (7)
OW70.0055 (6)0.0070 (10)0.0056 (6)0.0026 (6)0.0004 (5)0.0003 (6)
H7A0.0236 (17)0.029 (3)0.0120 (15)0.0112 (19)0.0011 (13)0.0031 (16)
H7B0.026 (2)0.014 (3)0.039 (3)0.0056 (19)0.0035 (19)0.010 (2)
OW80.0067 (6)0.0082 (10)0.0066 (7)0.0043 (7)0.0001 (5)0.0012 (7)
H8A0.028 (2)0.018 (2)0.0192 (18)0.0136 (18)0.0047 (15)0.0074 (16)
H8B0.030 (2)0.018 (2)0.0181 (17)0.0143 (18)0.0001 (15)0.0036 (17)
OW90.0059 (6)0.0078 (10)0.0053 (6)0.0030 (6)0.0001 (5)0.0001 (6)
H9A0.0220 (16)0.022 (2)0.0148 (16)0.0085 (17)0.0011 (13)0.0074 (16)
H9B0.0191 (16)0.012 (2)0.025 (2)0.0048 (15)0.0031 (14)0.0023 (17)
OW100.0067 (6)0.0096 (10)0.0055 (6)0.0045 (7)0.0002 (5)0.0002 (7)
H10A0.0220 (17)0.031 (3)0.0155 (16)0.0161 (19)0.0007 (14)0.0065 (17)
H10B0.0132 (13)0.028 (3)0.0219 (18)0.0099 (17)0.0047 (13)0.0022 (18)
OW110.0048 (6)0.0067 (10)0.0059 (7)0.0017 (6)0.0009 (5)0.0010 (6)
H11A0.0214 (17)0.012 (2)0.030 (2)0.0036 (16)0.0012 (16)0.0023 (18)
H11B0.0110 (13)0.024 (3)0.029 (2)0.0053 (15)0.0031 (14)0.003 (2)
Geometric parameters (Å, º) top
Mg1—OW2i2.053 (2)OW4—H4B0.977 (4)
Mg1—OW22.053 (2)OW5—H5A0.972 (5)
Mg1—OW1i2.0622 (19)OW5—H5B0.977 (4)
Mg1—OW12.0622 (19)OW6—H6A0.983 (4)
Mg1—OW3i2.066 (2)OW6—H6B0.972 (4)
Mg1—OW32.066 (2)Cr1—O41.637 (4)
OW1—H1A0.964 (5)Cr1—O11.643 (3)
OW1—H1B0.980 (5)Cr1—O31.660 (4)
OW2—H2A0.965 (5)Cr1—O21.667 (4)
OW2—H2B0.974 (4)OW7—H7A0.971 (5)
OW3—H3A0.972 (4)OW7—H7B0.957 (7)
OW3—H3B0.967 (6)OW8—H8A0.985 (6)
Mg2—OW52.045 (2)OW8—H8B0.974 (5)
Mg2—OW5ii2.045 (2)OW9—H9A0.984 (4)
Mg2—OW42.065 (2)OW9—H9B0.982 (6)
Mg2—OW4ii2.065 (2)OW10—H10A0.973 (5)
Mg2—OW6ii2.071 (2)OW10—H10B0.981 (4)
Mg2—OW62.071 (2)OW11—H11A0.969 (6)
OW4—H4A0.983 (4)OW11—H11B0.975 (4)
OW2i—Mg1—OW2179.999 (1)OW5—Mg2—OW6ii89.89 (9)
OW2i—Mg1—OW1i89.78 (8)OW5ii—Mg2—OW6ii90.11 (9)
OW2—Mg1—OW1i90.22 (8)OW4—Mg2—OW6ii89.43 (8)
OW2i—Mg1—OW190.22 (8)OW4ii—Mg2—OW6ii90.57 (8)
OW2—Mg1—OW189.78 (8)OW5—Mg2—OW690.11 (9)
OW1i—Mg1—OW1180.0OW5ii—Mg2—OW689.89 (9)
OW2i—Mg1—OW3i90.97 (9)OW4—Mg2—OW690.57 (8)
OW2—Mg1—OW3i89.03 (9)OW4ii—Mg2—OW689.43 (8)
OW1i—Mg1—OW3i92.78 (9)OW6ii—Mg2—OW6180.0
OW1—Mg1—OW3i87.22 (9)Mg2—OW4—H4A120.0 (3)
OW2i—Mg1—OW389.03 (9)Mg2—OW4—H4B128.5 (3)
OW2—Mg1—OW390.97 (9)H4A—OW4—H4B105.5 (4)
OW1i—Mg1—OW387.22 (9)Mg2—OW5—H5A128.0 (3)
OW1—Mg1—OW392.78 (9)Mg2—OW5—H5B125.8 (3)
OW3i—Mg1—OW3179.999 (1)H5A—OW5—H5B105.7 (4)
Mg1—OW1—H1A134.3 (3)Mg2—OW6—H6A116.6 (3)
Mg1—OW1—H1B119.2 (3)Mg2—OW6—H6B126.4 (4)
H1A—OW1—H1B105.8 (4)H6A—OW6—H6B105.1 (4)
Mg1—OW2—H2A127.3 (3)O4—Cr1—O1109.39 (17)
Mg1—OW2—H2B125.1 (3)O4—Cr1—O3108.85 (17)
H2A—OW2—H2B106.1 (4)O1—Cr1—O3109.2 (2)
Mg1—OW3—H3A126.5 (4)O4—Cr1—O2109.5 (2)
Mg1—OW3—H3B120.6 (3)O1—Cr1—O2110.17 (17)
H3A—OW3—H3B110.1 (5)O3—Cr1—O2109.79 (18)
OW5—Mg2—OW5ii180.0H7A—OW7—H7B104.8 (5)
OW5—Mg2—OW491.04 (9)H8A—OW8—H8B105.6 (5)
OW5ii—Mg2—OW488.96 (9)H9A—OW9—H9B104.0 (5)
OW5—Mg2—OW4ii88.96 (9)H10A—OW10—H10B106.1 (4)
OW5ii—Mg2—OW4ii91.03 (9)H11A—OW11—H11B106.1 (5)
OW4—Mg2—OW4ii180.0
Symmetry codes: (i) x+2, y, z; (ii) x+2, y, z+1.
Comparison of interatomic distances (Å) and angles (°) in the coordination polyhedra (X = S1 or Cr1), including calculated polyhedral volumes (Å3), between MgSO4.11H2O and MgCrO4.11H2O top
MgSO4.11H2OMgCrO4.11H2O
Mg1—OW12.0566 (9)2.062 (2)
Mg1—OW22.0617 (11)2.053 (2)
Mg1—OW32.0794 (10)2.066 (2)
Volume of M1 (Å3)11.743 (5)11.648 (12)
Mg2—OW42.0767 (10)2.065 (2)
Mg2—OW52.0458 (9)2.045 (2)
Mg2—OW62.0699 (11)2.071 (2)
Volume of M2 (Å3)11.722 (6)11.657 (12)
X—O11.467 (2)1.643 (3)
X—O21.473 (2)1.667 (4)
X—O31.486 (2)1.660 (4)
X—O41.488 (2)1.637 (4)
Volume of T1 (Å3)1.656 (1)2.312 (4)
OW1—Mg1—OW289.36 (4)89.78 (8)
OW1—Mg1—OW392.58 (4)92.78 (9)
OW2—Mg1—OW390.06 (4)90.97 (9)
OW4—Mg2—OW590.75 (4)91.04 (9)
OW4—Mg2—OW690.23 (4)90.57 (8)
OW5—Mg2—OW689.93 (4)90.11 (9)
O1—X—O2110.0 (1)110.2 (2)
O1—X—O3108.8 (1)109.2 (2)
O1—X—O4110.3 (1)109.4 (2)
O2—X—O3108.6 (1)109.8 (2)
O2—X—O4109.7 (1)109.5 (2)
O3—X—O4109.3 (1)108.9 (2)
Polyhedral volumes computed using Cayley–Menger determinants (Wirth & Dreiding, 2009).
Comparison of distances (Å) and angles (°) pertaining to the hydrogen-bond geometry in MgSO4.11H2O (upper half) and MgCrO4.11H2O (lower half) top
MgSO4.11H2O
D—HH···AD···AD—H···A
OW1—H1A···O10.964 (2)1.893 (2)2.8406 (14)167.1 (2)
OW1—H1B···OW8i0.975 (3)1.764 (3)2.7363 (16)174.0 (2)
OW2—H2A···O1ii0.965 (2)1.861 (3)2.8124 (15)168.2 (3)
OW2—H2B···OW80.974 (2)1.783 (2)2.7526 (14)173.8 (2)
OW3—H3A···OW110.965 (3)1.893 (3)2.8505 (17)171.3 (2)
OW3—H3B···O1iii0.972 (2)1.882 (2)2.8520 (12)175.5 (3)
OW4—H4A···OW9iii0.981 (2)1.731 (2)2.7108 (13)176.6 (2)
OW4—H4B···OW110.980 (3)1.793 (3)2.7603 (16)168.4 (2)
OW5—H5A···OW7i0.977 (3)1.774 (3)2.7461 (16)173.2 (3)
OW5—H5B···OW90.978 (3)1.755 (3)2.7283 (15)173.0 (2)
OW6—H6A···OW100.976 (3)1.753 (3)2.7212 (17)170.6 (2)
OW6—H6B···OW70.975 (2)1.815 (2)2.7825 (14)171.5 (3)
OW7—H7A···O20.978 (3)1.813 (3)2.7888 (16)175.0 (2)
OW7—H7B···OW4iv0.966 (2)2.096 (3)2.9558 (15)147.4 (3)
OW7—H7B···OW6v0.966 (2)2.484 (3)3.1694 (14)127.7 (3)
OW8—H8A···O30.973 (2)1.857 (2)2.8176 (13)168.7 (2)
OW8—H8B···O4vi0.975 (3)1.780 (3)2.7526 (15)175.1 (2)
OW9—H9A···O30.984 (3)1.737 (3)2.7036 (16)166.4 (2)
OW9—H9B···OW10vi0.983 (2)1.749 (2)2.7310 (13)177.0 (3)
OW10—H10A···O40.983 (2)1.718 (2)2.6877 (15)168.4 (2)
OW10—H10B···O2iii0.970 (2)1.797 (2)2.7455 (13)165.1 (2)
OW11—H11A···O2ii0.975 (2)1.881 (2)2.8359 (14)165.3 (3)
OW11—H11B···O30.975 (2)1.834 (2)2.8095 (14)178.3 (2)
MgCrO4.11H2O
OW1—H1A···O10.964 (5)1.950 (5)2.891 (3)164.7 (5)
OW1—H1B···OW8i0.980 (5)1.757 (4)2.732 (3)172.8 (6)
OW2—H2A···O1ii0.965 (5)1.865 (5)2.814 (3)167.4 (5)
OW2—H2B···OW80.974 (4)1.767 (4)2.740 (3)175.9 (6)
OW3—H3A···OW110.972 (4)1.872 (4)2.837 (3)171.7 (4)
OW3—H3B···O1iii0.967 (6)1.907 (5)2.870 (3)174.0 (5)
OW4—H4A···OW9iii0.983 (4)1.730 (4)2.712 (3)176.9 (5)
OW4—H4B···OW110.977 (4)1.801 (5)2.766 (3)168.4 (5)
OW5—H5A···OW7i0.972 (5)1.792 (5)2.757 (3)171.2 (5)
OW5—H5B···OW90.977 (4)1.747 (5)2.717 (3)171.2 (5)
OW6—H6A···OW100.983 (4)1.740 (4)2.716 (3)172.0 (4)
OW6—H6B···OW70.972 (4)1.805 (4)2.772 (3)172.5 (5)
OW7—H7A···O20.971 (5)1.793 (5)2.763 (3)177.7 (5)
OW7—H7B···OW4iv0.957 (7)2.269 (6)3.050 (4)138.3 (5)
OW7—H7B···OW6v0.957 (7)2.320 (7)3.085 (4)136.4 (5)
OW8—H8A···O30.985 (6)1.794 (6)2.770 (4)170.6 (4)
OW8—H8B···O4vi0.974 (5)1.764 (5)2.737 (3)176.0 (5)
OW9—H9A···O30.984 (4)1.708 (4)2.676 (3)167.3 (5)
OW9—H9B···OW10vi0.982 (6)1.748 (6)2.731 (4)178.6 (5)
OW10—H10A···O40.973 (5)1.734 (5)2.696 (3)169.2 (5)
OW10—H10B···O2iii0.981 (4)1.744 (5)2.714 (3)169.3 (6)
OW11—H11A···O2ii0.969 (6)1.857 (6)2.810 (3)167.1 (5)
OW11—H11B···O30.975 (4)1.802 (4)2.777 (3)179.4 (5)
See Fig. 3 for a graphical representation of these data.

Symmetry codes: (i) -x + 1, -y, -z; (ii) x + 1, y - 1, z; (iii) x + 1, y, z; (iv) x - 1, y + 1, z; (v) -x + 1, -y + 1, -z + 1; (vi) x, y - 1, z.
Principal axis magnitudes of the elastic strain tensor, and the corresponding direction cosines, computed from the change in unit-cell parameters on substitution of CrVI for SVI in MgSO4.11H2O. See Fig. 5 for a graphical representation of this information. top
This work,5–10 KFortes & Wood (2012),258 K
StrainDirectioncosinesStrainDirectioncosines
ε10.67 (7) %0.9648-0.0658-0.31500.885 (6) %0.9780-0.1675-0.1244
ε22.20 (9) %0.07480.99710.01662.182 (5) %0.18370.97390.1331
ε30.43 (7)%0.3130-0.03920.94890.458 (6) %0.0989-0.15300.9833
εV3.30 (14) %3.53 (1) %
 

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