metal-organic papers
Acta Cryst.(2005). E61, m1391–m1392 doi:10.1107/S1600536805019069 Zhanget al. [NiBr
2(C3H4N2)2(H2O)2]
m1391
Acta Crystallographica Section E Structure Reports Online
ISSN 1600-5368
Diaquadibromobis(1
H
-imidazole)nickel(II)
Hui Zhang,* Liang Fang and Runzhang Yuan
State Key Laboratory of Advanced Technology, for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, People’s Republic of China
Correspondence e-mail: huizhangskl@yahoo.com
Key indicators
Single-crystal X-ray study T= 223 K
Mean(C–C) = 0.003 A˚ Rfactor = 0.020 wRfactor = 0.051
Data-to-parameter ratio = 19.7
For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.
#2005 International Union of Crystallography Printed in Great Britain – all rights reserved
The structure of the title compound, [NiBr2(C3H4N2)2(H2O)2], consists of monomers with inversion symmetry. The three monodentate ligands (imidazole, bromine and aqua), together with their symmetry equivalents, define an almost perfect octahedral coordination. Hydrogen-bonding interactions via
the NH group of imidazole, Br and aqua H atoms lead to a three-dimensional network.
Comment
The structure of the title compound, (I), is composed of monomeric units possessing a crystallographically imposed center of symmetry (Fig. 1). The coordination environment of nickel is almost perfect octahedral (Table 1), corresponding to that observed in [NiCl2(Him)2(H2O)2] (Him is 1H-imidazole), (II) (Atria et al., 2003). However, (I) and (II) crystallize in different space groups, viz. monoclinic P21/c and ortho-rhombicPbca, respectively.
In (I), the three potentially active H atoms,viz. imidazole H2 and aqua H1Wand H2Watoms, are engaged in hydrogen bonds with the Br atom, which acts as the sole acceptor for all three interactions (Table 2). The O—H Br hydrogen bonds
[image:1.610.255.410.383.507.2] [image:1.610.206.461.584.723.2]Received 20 May 2005 Accepted 15 June 2005 Online 24 June 2005
Figure 1
View of (I) shown with 50% probability displacement ellipsoids. Atoms labelled with the suffix a are at symmetry position (1
(Fig. 2, dashed red lines) link monomers along the band c
axes, thus defining two-dimensional arrays, which are further linked by the N—H Br hydrogen bonds (Fig. 2, dashed blue lines), to form a three-dimensional network.
Experimental
Crystals of (I) were obtained from NiBr26H2O (5 mmol) and 1H -imidazole (5 mmol) in aqueous solution (30 ml) at room temperature. After a few days, green prismatic crystals appeared.
Crystal data
[NiBr2(C3H4N2)2(H2O)2]
Mr= 390.69
Monoclinic,P21=c
a= 7.8000 (18) A˚
b= 9.366 (2) A˚
c= 8.474 (2) A˚
= 96.114 (4)
V= 615.6 (2) A˚3
Z= 2
Dx= 2.108 Mg m
3
MoKradiation Cell parameters from 1538
reflections
= 2.6–28.3
= 8.05 mm1
T= 223 (2) K Prism, green
0.360.200.16 mm
Data collection
Bruker SMART APEX CCD diffractometer
!scans
Absorption correction: multi-scan (SADABSinSAINT; Bruker, 1998)
Tmin= 0.16,Tmax= 0.28
8270 measured reflections
1538 independent reflections 1414 reflections withI> 2(I)
Rint= 0.039 max= 28.3
h=10!10
k=12!12
l=11!11
Refinement
Refinement onF2
R[F2> 2(F2)] = 0.020
wR(F2) = 0.051
S= 1.05 1538 reflections 78 parameters
H atoms treated by a mixture of independent and constrained refinement
w= 1/[2(F
o2) + (0.0269P)2
+ 0.0562P]
whereP= (Fo2+ 2Fc2)/3
(/)max< 0.001 max= 0.34 e A˚
3 min=0.63 e A˚
3
Table 1
Selected geometric parameters (A˚ ,).
Ni1—N1 2.0557 (16) Ni1—O1 2.0910 (15)
Ni1—Br1 2.6184 (6)
N1—Ni1—O1 88.53 (6) N1—Ni1—Br1 89.59 (5)
O1—Ni1—Br1 90.15 (5)
Table 2
Hydrogen-bond geometry (A˚ ,).
D—H A D—H H A D A D—H A
O1—H1W Br1i
0.79 (3) 2.56 (3) 3.3356 (16) 168 (3) O1—H2W Br1ii
0.81 (3) 2.55 (3) 3.3273 (17) 164 (2) N2—H2 Br1iii 0.87 2.64 3.4782 (19) 162
Symmetry codes: (i)xþ1;yþ1
2;zþ52; (ii)x;y12;zþ12; (iii)x;y;zþ2.
The imidazole H atoms were constrained to an ideal geometry, with C—H and N—H distances of 0.94 and 0.87 A˚ , respectively. Aqua H atoms were located in a difference Fourier map and their positions were refined freely. All H atoms were treated as isotropic, with
Uiso(H) = 1.2Ueq(C,N,O).
Data collection:SMART(Bruker, 1998); cell refinement:SAINT
(Bruker, 1998); data reduction:SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure:SHELXTL; molecular graphics:ORTEP-3(Farrugia, 1997) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication:SHELXTL.
HZ thanks DAAD for a scholarship and Mr Klaus Kruse for the data collection.
References
Atria, A. M., Corte´s, P., Garland, M. T. & Baggio, R. (2003).Acta Cryst.C59, m396–m398.
Brandenburg, K. (1999).DIAMOND. Release 2.1e. Crystal Impact GbR, Bonn, Germany.
Bruker (1998).SMART,SAINT, andSADABSinSAINT. Bruker AXS Inc., Madison, Wisconsin, USA.
Farrugia, L. J. (1997).J. Appl. Cryst.30, 565.
[image:2.610.313.566.72.349.2]Sheldrick, G. M. (1997).SHELXTL. University of Go¨ttingen, Germany.
Figure 2
supporting information
sup-1
Acta Cryst. (2005). E61, m1391–m1392
supporting information
Acta Cryst. (2005). E61, m1391–m1392 [https://doi.org/10.1107/S1600536805019069]
Diaquadibromobis(1
H
-imidazole)nickel(II)
Hui Zhang, Liang Fang and Runzhang Yuan
Diaquadibromobis(1H-imidazole)nickel(II)
Crystal data
[NiBr2(C3H4N2)2(H2O)2] Mr = 390.69
Monoclinic, P21/c
Hall symbol: -P 2ybc
a = 7.8000 (18) Å
b = 9.366 (2) Å
c = 8.474 (2) Å
β = 96.114 (4)°
V = 615.6 (2) Å3
Z = 2
F(000) = 380
Dx = 2.108 Mg m−3
Mo Kα radiation, λ = 0.71073 Å
Cell parameters from 1538 reflections
θ = 2.6–28.3°
µ = 8.05 mm−1
T = 223 K
Prism, green
0.36 × 0.20 × 0.16 mm
Data collection
Bruker AXS APEX CCD diffractometer
Radiation source: fine-focus sealed tube Graphite monochromator
ω scans
Absorption correction: multi-scan (SADABS in SAINT; Bruker, 1998)
Tmin = 0.16, Tmax = 0.28
8270 measured reflections 1538 independent reflections 1414 reflections with I > 2σ(I)
Rint = 0.039
θmax = 28.3°, θmin = 2.6°
h = −10→10
k = −12→12
l = −11→11
Refinement
Refinement on F2
Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.020 wR(F2) = 0.051
S = 1.05
1538 reflections 78 parameters 0 restraints
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
Hydrogen site location: inferred from neighbouring sites
H atoms treated by a mixture of independent and constrained refinement
w = 1/[σ2(F
o2) + (0.0269P)2 + 0.0562P]
where P = (Fo2 + 2Fc2)/3
(Δ/σ)max < 0.001
Δρmax = 0.34 e Å−3
Δρmin = −0.63 e Å−3
Special details
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)
x y z Uiso*/Ueq
Ni1 0.5000 0.0000 1.0000 0.01679 (9)
Br1 0.39147 (2) −0.264724 (19) 0.99031 (2) 0.02118 (8)
N1 0.25951 (19) 0.06572 (18) 0.9048 (2) 0.0221 (3)
N2 −0.0015 (2) 0.1547 (2) 0.8858 (3) 0.0389 (5)
H2 −0.0911 0.2019 0.9101 0.047*
C3 0.1503 (3) 0.1427 (2) 0.9765 (3) 0.0320 (5)
H3 0.1749 0.1838 1.0776 0.038*
C4 0.1721 (3) 0.0257 (3) 0.7620 (3) 0.0316 (5)
H4 0.2175 −0.0308 0.6847 0.038*
C5 0.0098 (3) 0.0805 (3) 0.7501 (3) 0.0392 (6)
H5 −0.0768 0.0693 0.6651 0.047*
O1 0.41887 (19) 0.02412 (18) 1.22586 (17) 0.0233 (3)
H1W 0.460 (3) 0.084 (3) 1.283 (3) 0.037 (8)*
H2W 0.420 (3) −0.050 (3) 1.275 (3) 0.039 (8)*
Atomic displacement parameters (Å2)
U11 U22 U33 U12 U13 U23
Ni1 0.01500 (16) 0.01698 (17) 0.01828 (17) 0.00154 (12) 0.00120 (12) 0.00005 (12)
Br1 0.02362 (12) 0.01741 (11) 0.02244 (12) −0.00084 (7) 0.00210 (8) −0.00044 (7)
N1 0.0178 (7) 0.0212 (8) 0.0273 (8) 0.0030 (6) 0.0022 (6) 0.0022 (7)
N2 0.0207 (9) 0.0381 (11) 0.0585 (14) 0.0122 (8) 0.0071 (8) 0.0101 (10)
C3 0.0267 (10) 0.0297 (12) 0.0401 (12) 0.0078 (9) 0.0048 (9) −0.0006 (9)
C4 0.0232 (10) 0.0435 (13) 0.0273 (11) 0.0037 (9) −0.0013 (8) −0.0005 (9)
C5 0.0226 (10) 0.0538 (15) 0.0396 (13) 0.0044 (10) −0.0047 (9) 0.0111 (12)
O1 0.0265 (7) 0.0227 (7) 0.0205 (7) −0.0028 (6) 0.0023 (6) −0.0013 (6)
Geometric parameters (Å, º)
Ni1—N1 2.0557 (16) N2—C5 1.354 (3)
Ni1—N1i 2.0557 (16) N2—H2 0.8700
Ni1—O1 2.0910 (15) C3—H3 0.9400
Ni1—O1i 2.0910 (15) C4—C5 1.360 (3)
Ni1—Br1 2.6184 (6) C4—H4 0.9400
Ni1—Br1i 2.6184 (6) C5—H5 0.9400
N1—C3 1.313 (3) O1—H1W 0.79 (3)
N1—C4 1.376 (3) O1—H2W 0.81 (3)
N2—C3 1.346 (3)
supporting information
sup-3
Acta Cryst. (2005). E61, m1391–m1392
N1—Ni1—O1 88.53 (6) C3—N2—C5 108.01 (18)
N1i—Ni1—O1 91.47 (6) C3—N2—H2 126.0
N1—Ni1—O1i 91.47 (6) C5—N2—H2 126.0
N1i—Ni1—O1i 88.53 (6) N1—C3—N2 110.9 (2)
O1—Ni1—O1i 180.0 N1—C3—H3 124.6
N1—Ni1—Br1 89.59 (5) N2—C3—H3 124.6
N1i—Ni1—Br1 90.41 (5) C5—C4—N1 109.4 (2)
O1—Ni1—Br1 90.15 (5) C5—C4—H4 125.3
O1i—Ni1—Br1 89.85 (5) N1—C4—H4 125.3
N1—Ni1—Br1i 90.41 (5) N2—C5—C4 106.0 (2)
N1i—Ni1—Br1i 89.59 (5) N2—C5—H5 127.0
O1—Ni1—Br1i 89.85 (5) C4—C5—H5 127.0
O1i—Ni1—Br1i 90.15 (5) Ni1—O1—H1W 119.8 (18)
Br1—Ni1—Br1i 180.0 Ni1—O1—H2W 113.3 (19)
C3—N1—C4 105.75 (18) H1W—O1—H2W 108 (3)
C3—N1—Ni1 126.32 (15)
Symmetry code: (i) −x+1, −y, −z+2.
Hydrogen-bond geometry (Å, º)
D—H···A D—H H···A D···A D—H···A
O1—H1W···Br1ii 0.79 (3) 2.56 (3) 3.3356 (16) 168 (3)
O1—H2W···Br1iii 0.81 (3) 2.55 (3) 3.3273 (17) 164 (2)
N2—H2···Br1iv 0.87 2.64 3.4782 (19) 162