(IUCr) Low-temperature phase of hexaguanidinium heptamolybdate monohydrate

Volume 64
Part 5
Pages m614-m615
May 2008

Received 4 March 2008
Accepted 26 March 2008
Online 2 April 2008

Key indicators
Single-crystal X-ray study
T = 173 K
Mean (N-C) = 0.007 Å
R = 0.054
wR = 0.165
Data-to-parameter ratio = 31.3
Details

Low-temperature phase of hexaguanidinium heptamolybdate monohydrate

Santiago Reinoso,^a Michael H. Dickman,^a ^* Antonia Praetorius ^a and Ulrich Kortz*^a

^aSchool of Engineering and Science, Jacobs University Bremen, PO Box 750561, 28725 Bremen, Germany
Correspondence e-mail: m.dickman@jacobs-university.de

The crystal structure of the title compound, [C(NH₂)₃]₆[Mo₇O₂₄]·H₂O, previously determined at room temperature in the monoclinic space group C2/c from Weissenberg techniques [Don & Weakley (1981). Acta Cryst. B37, 451-453], has been redetermined from low-temperature single-crystal data in the monoclinic space group P2₁/c. The asymmetric unit contains one heptamolybdate anion, six guanidinium cations and one water molecule of hydration. The anions and cations are linked by an extensive network of N-HO hydrogen bonds.

Related literature

For the previous determination of the title compound in the monoclinic space group C2/c, see: Don & Weakley (1981). For an example of a structurally characterized [Mo₇O₂₄]^6- anion, see: Kortz & Pope (1995). For more information about isopolymolybdates and polyoxometalates in general, see: Pope (1983).

Experimental

Crystal data

(CH₆N₃)₆[Mo₇O₂₄].H₂O
M_r = 1434.12
Monoclinic, P 2₁ /c
a = 11.9402 (6) Å
b = 15.9131 (9) Å
c = 19.8223 (13) Å
= 92.312 (4)°
V = 3763.3 (4) Å³
Z = 4
Mo K radiation
= 2.37 mm^-1
T = 173 (2) K
0.17 × 0.17 × 0.08 mm

Data collection

Bruker X8 APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (APEX2; Bruker, 2005) T_min = 0.689, T_max = 0.833
153838 measured reflections
15842 independent reflections
9689 reflections with I > 2s(I)
R_int = 0.150

Refinement

R[F² > 2(F²)] = 0.053
wR(F²) = 0.164
S = 1.05
15842 reflections
506 parameters
H-atom parameters constrained
_max = 1.77 e Å^-3
_min = -2.33 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
N11-H11AO1W	0.88	1.90	2.765 (6)	168
N11-H11BO3A	0.88	2.35	3.091 (6)	142
N12-H12AO2Aⁱ	0.88	2.00	2.845 (5)	160
N12-H12BO5B	0.88	2.14	2.903 (5)	145
N13-H13AO6Aⁱⁱ	0.88	1.96	2.828 (5)	169
N13-H13BO3B	0.88	2.23	2.930 (5)	136
N14-H14BO13	0.88	1.93	2.774 (4)	159
N14-H14AO57ⁱⁱⁱ	0.88	1.98	2.814 (4)	159
N15-H15AO2B^iv	0.88	2.03	2.843 (5)	153
N15-H15BO3A^v	0.88	2.13	2.866 (5)	141
N15-H15BO34^v	0.88	2.62	3.302 (5)	135
N16-H16BO1Aⁱⁱ	0.88	2.13	2.967 (5)	159
N16-H16AO45^vi	0.88	2.18	2.977 (5)	151
N21-H21AO1B^vi	0.88	2.18	3.006 (5)	156
N21-H21AO2B^vi	0.88	2.40	2.926 (5)	118
N21-H21BO3A	0.88	2.22	2.992 (5)	147
N22-H22AO36^vii	0.88	2.32	3.087 (5)	145
N22-H22AO467^vii	0.88	2.50	3.216 (5)	139
N22-H22AO6B^vii	0.88	2.64	3.290 (5)	131
N22-H22BO25	0.88	2.10	2.977 (5)	177
N23-H23AO36	0.88	2.07	2.937 (5)	169
N23-H23BO25^vi	0.88	2.26	3.023 (5)	145
N23-H23BO124^vi	0.88	2.50	3.219 (5)	140
N24-H24AO13	0.88	2.45	3.154 (5)	137
N24-H24AO3A	0.88	2.50	3.186 (5)	135
N24-H24BO12^viii	0.88	2.09	2.855 (5)	145
N25-H25AO34^v	0.88	2.22	2.990 (5)	146
N25-H25BO7Aⁱⁱⁱ	0.88	2.08	2.931 (5)	162
N26-H26AO3Bⁱⁱ	0.88	1.98	2.859 (5)	175
N26-H26BO1Wⁱⁱ	0.88	2.50	3.084 (6)	124
N26-H26BO6A	0.88	2.57	3.197 (5)	129
N31-H31AO1B^vi	0.88	2.50	3.248 (6)	143
N31-H31BO5A^ix	0.88	2.38	3.188 (6)	152
N32-H32AN34^x	0.88	2.50	3.242 (6)	143
N32-H32BO467^vii	0.88	2.02	2.864 (5)	160
N33-H33AN24^vi	0.88	2.60	3.334 (6)	142
N33-H33BO124^vi	0.88	2.02	2.867 (5)	160
N34-H34BO67^viii	0.88	1.94	2.776 (5)	157
N34-H34AO57ⁱⁱⁱ	0.88	2.44	3.154 (5)	139
N34-H34AO5Aⁱⁱⁱ	0.88	2.55	3.195 (5)	131
N35-H35AO2A^iv	0.88	2.29	3.040 (5)	144
N35-H35BO5Bⁱⁱⁱ	0.88	1.98	2.849 (5)	170
N36-H36AO5A^vi	0.88	2.16	2.913 (5)	144
N36-H36BO6B	0.88	2.13	2.868 (5)	141
O1W-H1OWO6Bⁱⁱⁱ	0.86	2.22	2.948 (5)	142
O1W-H1OWO7Bⁱⁱⁱ	0.86	2.44	3.086 (5)	133
O1W-H2OWO5A^ix	0.86	2.35	2.973 (5)	130
Symmetry codes: (i) -x+1, -y, -z; (ii) -x, -y, -z+1; (iii) x-1, y, z; (iv) -x, -y, -z; (v) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (vi) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (vii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (viii) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ix) $[x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (x) $[x+1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and WINGX Farrugia (1999)..

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: MG2049 ).

Acknowledgements

SR thanks Gobierno Vasco/Eusko Jaurlaritza for his postdoctoral fellowship.

References

Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.
Don, A. & Weakley, T. J. R. (1981). Acta Cryst. B37, 451-453.
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.
Kortz, U. & Pope, M. T. (1995). Acta Cryst. C51, 1717-1719.
Pope, M. T. (1983). Heteropoly and Isopoly Oxometalates. Berlin: Springer-Verlag.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.

metal-organic compounds