inorganic compounds Chromous hydrazine sulfate

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1 inorganic compounds Acta Crystallographica Section C Crystal Structure Communications ISSN Chromous hydrazine sulfate Adrian W. Parkins,* Paul D. Prince, Robert A. L. Smith and Jonathan W. Steed Department of Chemistry, King's College London, Strand, London WC2R 2LS, England Correspondence adrian.parkins@kcl.ac.uk Received 14 August 2000 Accepted 10 January 2001 The title compound, catena-poly[dihydraziniochromium(ii)- di--sulfato-o:o 0 ], [Cr(N 2 H 5 ) 2 (SO 4 ) 2 ], was studied at 100 K and contains chains of chromium(ii) ions linked by pairs of sulfate anions and coordinated to hydrazinium ions. The unique Cr atom lies on an inversion centre. All ve H atoms were experimentally located and are involved in hydrogen bonding to O atoms of the sulfate groups. Comment Chromous hydrazine sulfate, (I), was originally reported by Traube & Passarge (1913) and is unusual in that it is an airstable complex of chromium(ii). Although often encountered as a preparative experiment in undergraduate practical courses (Adams & Raynor, 1965; Palmer, 1954), the structure of chromous hydrazine sulfate has never been determined, as it is usually obtained as a microcrystalline solid unsuitable for single-crystal X-ray diffraction. The structure of zinc hydrazine sulfate, (II), has been reported and shows chains of zinc(ii) cations with bridging sulfate anions and coordinated hydrazinium cations. Both compounds are best formulated as [M(N 2 H 5 ) 2 (SO 4 ) 2 ] (Prout & Powell, 1961). The cell dimensions of a number of metal hydrazine sulfates, including the Cr II complex, were reported and it was suggested that the compounds were all of the same structural type (Hand & Prout, 1966). (1913) without water of crystallization is con rmed by our crystallographic study. Both Adams & Raynor (1965) and Palmer (1954) formulated the compound as a hydrate. The present crystal is triclinic with dimensions close to those reported previously (Hand & Prout, 1966). The structure of (I) is very similar to that of the analogous zinc compound and consists of chains of chromium(ii) cations linked by pairs of sulfate anions (Fig. 1). The chains are parallel to the b axis and the CrÐCr distance is the same as the b-cell dimension, i.e (5) A Ê. Selected geometric parameters are given in Table 1. The structure is centrosymmetric, with the chromium(ii) ion on a centre of symmetry, and the asymmetric unit is one half a formula unit, i.e. 1 2 [Cr(N 2 H 5 ) 2 (SO 4 ) 2 ]. As with the zinc analogue, there is pronounced asymmetry in the CrÐO distances to the sulfate ion, (17) and (19) A Ê. Asymmetry of this type is not unusual (Hathaway, 1987). Each chromium(ii) ion is also coordinated to two hydrazinium (N 2 H 5 + ) cations. We have used the same choice of axes as Prout & Powell (1961), and labelled the atoms in a corresponding manner, except that O1 and O2 have been interchanged, so that CrÐO1 remains the `short' metal±oxygen bond in both structures, and have given symmetry equivalent coordinates for N1 and N2 to achieve connectivity within the asymmetric unit. All ve H atoms are involved in hydrogen bonding to O atoms of sulfate groups. Fig. 1 shows the hydrogen bonding within the chromium/sulfate chains and Fig. 2 the hydrogen bonding between the chains. While atoms H1 to H4 are only involved in interaction with one O atom, H5 has interactions with O1 within the chain and with O1 and O2 from an adjacent chain. Atom H5 is therefore involved in hydrogen bonding to three O atoms in what has been described as four-centre bonding (Jeffrey, 1997). The hydrogen bonding in (I) is similar to that suggested for (II), although there is no H atom linking N1 and O4 of the same chain. The NÐHO distances are close to those observed previously for NÐH hydrogen bonds to the O atoms of sulfate groups (Chertanova & Pascard, 1996). Since the structure of (II) was initially reported, several structures of the general formula [Zn(N 2 H 4 ) 2 X 2 ], in which X is On one occasion, we were fortunate enough to obtain good quality crystals of (I) from a preparation carried out in a practical class. The sample was prepared by reacting chromous acetate with hydrazine sulfate in dilute sulfuric acid (Adams & Raynor, 1965). The original formulation of Traube & Passarge Figure 1 View of a fragment of a chromium/sulfate chain of (I) showing the hydrogen bonding within the chain which runs along the b axis, and the atom-numbering scheme. Displacement ellipsoids of non-h atoms are shown at the 70% probability level. The symmetry codes are as given in Tables 1 and 2, with the addition of (iii) x, y, z. 670 # 2001 International Union of Crystallography Printed in Great Britain ± all rights reserved Acta Cryst. (2001). C57, 670±671

2 inorganic compounds a monovalent anion, have been investigated. In contrast to the sulfate, the complexes with mononegative anions have unprotonated bridging hydrazine molecules, with the anions completing a pseudo-octahedral geometry at the metal (Ferrari et al., 1965, and references therein). Table 1 Selected geometric parameters (A Ê, ). CrÐO1 i (17) CrÐO (19) CrÐN (2) SÐO (18) SÐO (2) SÐO (18) SÐO (18) N1ÐN (3) O1 i ÐCrÐN (8) O1 i ÐCrÐO (7) N1ÐCrÐO (8) O2ÐSÐO (11) O2ÐSÐO (11) O4ÐSÐO (11) O2ÐSÐO (11) O4ÐSÐO (10) O3ÐSÐO (10) SÐO1ÐCr iv (11) SÐO2ÐCr (11) N2ÐN1ÐCr (16) Symmetry codes: (i) x; y 1; z; (iv) x; 1 y; z. Table 2 Hydrogen-bonding geometry (A Ê, ). DÐHA DÐH HA DA DÐHA Figure 2 View of (I) showing the hydrogen bonding between adjacent chains and the outline of the unit cell. Displacement ellipsoids of non-h atoms are shown at the 70% probability level. The symmetry codes are as given in Tables 1 and 2, with the addition of (viii) 1 x, 1 y, 1 z. Experimental Chromous hydrazine sulfate was prepared by reacting chromous acetate with hydrazine sulfate in dilute sulfuric acid (Adams & Raynor, 1965) and was crystallized from the reaction medium. Crystal data [Cr(N 2 H 5 ) 2 (SO 4 ) 2 ] M r = Triclinic, P1 a = (3) A Ê b = (5) A Ê c = (6) A Ê = (2) = (2) = (2) V = (3) A Ê 3 Data collection Nonius KappaCCD area-detector diffractometer 2 ' frames Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997) T min = 0.567, T max = measured re ections Re nement Re nement on F 2 R[F 2 >2(F 2 )] = wr(f 2 ) = S = re ections 91 parameters Z =1 D x = Mg m 3 Mo K radiation Cell parameters from 1336 re ections = 3.6±26.0 = 1.83 mm 1 T = 100 (2) K Rectangular prism, blue mm 786 independent re ections 751 re ections with I > 2(I) R int = max = 26.0 h = 8! 8 k = 6! 6 l = 6! 7 Intensity decay: none All H-atom parameters re ned w = 1/[ 2 (F o 2 ) P] where P =(F o 2 +2F c 2 )/3 (/) max < max = 0.32 e A Ê 3 min = 0.58 e A Ê 3 The H atoms were located in the difference map and were re ned with unconstrained isotropic displacement parameters, but with a xed NÐH distance of 0.88 A Ê. When the determination was carried out, the diffractometer was incapable of collecting cusp data, and so N1ÐH1O3 v 0.88 (3) 2.01 (3) (3) 164 (3) N1ÐH2O4 vi 0.88 (3) 2.18 (2) (3) 150 (3) N2ÐH3O (3) 1.91 (2) (3) 158 (3) N2ÐH4O3 vi 0.88 (3) 1.92 (2) (3) 168 (3) N2ÐH5O2 vii 0.88 (3) 2.32 (2) (3) 142 (3) N2ÐH5O1 ii 0.88 (3) 2.38 (3) (3) 114 (2) N2ÐH5O1 v 0.88 (3) 2.51 (3) (3) 117 (3) Symmetry codes: (ii) x; 1 y; z; (v) x; y 1; z 1; (vi) 1 x; 1 y; z; (vii) x; y; z 1. we report a comparatively low completeness of possible data. The somewhat low re ection/parameter ratio is caused by the re nement of parameters for the H atoms. Data collection: COLLECT (Hooft, 1998); cell re nement: DENZO±SMN (Otwinowski & Minor, 1997); data reduction: DENZO±SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to re ne structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XSeed (Barbour, 1999) and ORTEP-3 (Farrugia, 1997). We thank the EPSRC and King's College London for funding the diffractometer system. Supplementary data for this paper are available from the IUCr electronic archives (Reference: BM1427). Services for accessing these data are described at the back of the journal. References Adams, D. M. & Raynor, J. B. (1965). Advanced Practical Inorganic Chemistry, p. 92. London: Wiley. Barbour, L. J. (1999). Xseed. University of Missouri±Columbia, Missouri, USA. Chertanova, L. & Pascard, C. (1996). Acta Cryst. B52, 677±684. Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. Ferrari, A., Braibanti, A., Bigliardi, G. & Lanfredi, A. M. (1965). Acta Cryst. 19, 548±555. Hand, D. W. & Prout, C. K. (1966). J. Chem. Soc. A, pp. 168±171. Hathaway, B. J. (1987). Comprehensive Coordination Chemistry, Vol. 2, p Oxford: Pergamon. Hooft, R. (1998). COLLECT. Nonius BV, Delft, The Netherlands. Jeffrey, G. A. (1997). An Introduction to Hydrogen Bonding, p. 25. New York: Oxford University Press. Otwinowski, Z. & Minor, W. (1997). Methods Enzymol. 276, 307±326. Palmer, W. G. (1954). Experimental Inorganic Chemistry, p Cambridge University Press. Prout, C. K. & Powell, H. M. (1961). J. Chem. Soc. pp. 4177±4182. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of GoÈttingen, Germany. Traube, W. & Passarge, W. (1913). Chem. Ber. 46, 1505±1508. Acta Cryst. (2001). C57, 670±671 Adrian W. Parkins et al. [Cr(N 2 H 5 ) 2 (SO 4 ) 2 ] 671

3 [doi: /s ] Chromous hydrazine sulfate Adrian W. Parkins, Paul D. Prince, Robert A. L. Smith and Jonathan W. Steed Computing details Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 1999) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97. Dihydraziniumchromium(II) sulfate Crystal data [Cr(N 2 H 5 ) 2 (SO 4 ) 2 ] M r = Triclinic, P1 a = (3) Å b = (5) Å c = (6) Å α = (2) β = (2) γ = (2) V = (3) Å 3 Data collection Nonius KappaCCD area-detector diffractometer Radiation source: fine-focus sealed tube Graphite monochromator Detector resolution: 9.09 pixels mm -1 2 φ frames scans Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997) T min = 0.567, T max = Refinement Refinement on F 2 Least-squares matrix: full R[F 2 > 2σ(F 2 )] = wr(f 2 ) = S = reflections 91 parameters 5 restraints Primary atom site location: structure-invariant direct methods Z = 1 F(000) = 158 D x = Mg m 3 Mo Kα radiation, λ = Å Cell parameters from 1336 reflections θ = µ = 1.83 mm 1 T = 100 K Rectangular prism, blue mm 1336 measured reflections 786 independent reflections 751 reflections with I > 2σ(I) R int = θ max = 26.0, θ min = 3.6 h = 8 8 k = 6 6 l = 6 7 Secondary atom site location: difference Fourier map Hydrogen site location: difference Fourier map All H-atom parameters refined w = 1/[σ 2 (F o2 ) P] where P = (F o 2 + 2F c2 )/3 (Δ/σ) max < Δρ max = 0.32 e Å 3 Δρ min = 0.58 e Å 3 sup-1

4 Special details 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 ) x y z U iso */U eq Cr (2) S (9) (12) (10) (2) O (3) (4) (3) (4) O (3) (4) (3) (4) O (3) (4) (3) (4) O (3) (4) (3) (4) N (3) (5) (4) (5) N (3) (5) (4) (5) H (5) (4) (5) (8)* H (3) (7) (6) (10)* H (5) (3) (5) (9)* H (2) (7) (5) (8)* H (3) (7) (4) (8)* Atomic displacement parameters (Å 2 ) U 11 U 22 U 33 U 12 U 13 U 23 Cr (4) (4) (3) (3) (2) (2) S (4) (4) (3) (3) (2) (2) O (9) (11) (9) (8) (7) (7) O (9) (11) (9) (8) (7) (7) O (9) (10) (9) (8) (7) (7) O (9) (11) (9) (8) (7) (7) N (11) (13) (11) (10) (8) (8) N (11) (14) (11) (10) (8) (9) Geometric parameters (Å, º) Cr O1 i (17) S O (18) Cr O1 ii (17) S O (2) Cr O (19) S O (18) Cr O2 iii (19) S O (18) Cr N1 iii (2) O1 Cr iv (17) Cr N (2) N1 N (3) O1 i Cr O1 ii (9) N1 iii Cr O2 iii (8) sup-2

5 O1 i Cr N1 iii (8) N1 Cr O2 iii (8) O1 ii Cr N1 iii (8) O2 Cr O2 iii (11) O1 i Cr N (8) O2 S O (11) O1 ii Cr N (8) O2 S O (11) N1 iii Cr N (17) O4 S O (11) O1 i Cr O (7) O2 S O (11) O1 ii Cr O (7) O4 S O (10) N1 iii Cr O (8) O3 S O (10) N1 Cr O (8) S O1 Cr iv (11) O1 i Cr O2 iii (7) S O2 Cr (11) O1 ii Cr O2 iii (7) N2 N1 Cr (16) O2 S O1 Cr iv (16) O1 ii Cr O2 S (19) O4 S O1 Cr iv (17) N1 iii Cr O2 S (19) O3 S O1 Cr iv (13) N1 Cr O2 S (19) O4 S O2 Cr 4.5 (2) O1 i Cr N1 N (17) O3 S O2 Cr (17) O1 ii Cr N1 N (17) O1 S O2 Cr (17) O2 Cr N1 N (18) O1 i Cr O2 S (19) O2 iii Cr N1 N (18) Symmetry codes: (i) x, y 1, z; (ii) x, y+1, z; (iii) x, y, z; (iv) x, y+1, z. Hydrogen-bond geometry (Å, º) D H A D H H A D A D H A N1 H1 O3 v 0.88 (3) 2.01 (3) (3) 164 (3) N1 H2 O4 vi 0.88 (3) 2.18 (2) (3) 150 (3) N2 H3 O (3) 1.91 (2) (3) 158 (3) N2 H4 O3 vi 0.88 (3) 1.92 (2) (3) 168 (3) N2 H5 O2 vii 0.88 (3) 2.32 (2) (3) 142 (3) N2 H5 O1 ii 0.88 (3) 2.38 (3) (3) 114 (2) N2 H5 O1 v 0.88 (3) 2.51 (3) (3) 117 (3) Symmetry codes: (ii) x, y+1, z; (v) x, y 1, z 1; (vi) x+1, y+1, z; (vii) x, y, z 1. sup-3