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Volume 68 
Part 11 
Page i82  
November 2012  

Received 14 October 2012
Accepted 20 October 2012
Online 27 October 2012

Key indicators
Single-crystal X-ray study
T = 293 K
Mean [sigma](As-O) = 0.002 Å
R = 0.022
wR = 0.055
Data-to-parameter ratio = 16.6
Details
Open access

Redetermination of (NH4)2HAsO4

aInstitute for Chemical Technologies and Analytics, Division of Structural Chemistry, Vienna University of Technology, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria
Correspondence e-mail: mweil@mail.zserv.tuwien.ac.at

In comparison with the original determination based on Weissenberg film data [Khan et al. (1970[Khan, A. A., Straumanis, E. & James, W. J. (1970). Acta Cryst. B26, 1889-1892.]). Acta Cryst. B26, 1889-1892], the current redetermination of diammonium hydrogenarsenate(V) reveals all atoms with anisotropic displacement parameters and all H atoms localized. This allowed an unambiguous assignment of the hydrogen-bonding pattern, which is similar to that of the isotypic phosphate analogue (NH4)2HPO4. The structure of the title compound consists of slightly distorted AsO3(OH) and NH4 tetrahedra, linked into a three-dimensional structure by an extensive network of O-H...O and N-H...O hydrogen bonds.

Related literature

For the previous determination of (NH4)2HAsO4, see: Khan et al. (1970[Khan, A. A., Straumanis, E. & James, W. J. (1970). Acta Cryst. B26, 1889-1892.]). The arsenate compound is isotypic with the phosphate analogue (NH4)2HPO4 (Khan et al., 1972[Khan, A. A., Roux, J. P. & James, W. J. (1972). Acta Cryst. B28, 2065-2069.]), for which another modification with Z' = 2 has also recently been described (Kunz et al., 2010[Kunz, P. C., Wetzel, C. & Spingler, B. (2010). Acta Cryst. E66, i26-i27.]).

Experimental

Crystal data
  • (NH4)2HAsO4

  • Mr = 176.01

  • Monoclinic, P 21 /c

  • a = 11.3426 (4) Å

  • b = 6.8512 (3) Å

  • c = 8.1130 (3) Å

  • [beta] = 113.784 (4)°

  • V = 576.92 (4) Å3

  • Z = 4

  • Mo K[alpha] radiation

  • [mu] = 5.82 mm-1

  • T = 293 K

  • 0.14 × 0.12 × 0.02 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) Tmin = 0.496, Tmax = 0.873

  • 6318 measured reflections

  • 1674 independent reflections

  • 1413 reflections with I > 2[sigma](I)

  • Rint = 0.033

Refinement
  • R[F2 > 2[sigma](F2)] = 0.022

  • wR(F2) = 0.055

  • S = 1.04

  • 1676 reflections

  • 101 parameters

  • All H-atom parameters refined

  • [Delta][rho]max = 0.59 e Å-3

  • [Delta][rho]min = -0.84 e Å-3

Table 1
Hydrogen-bond geometry (Å, °)

D-H...A D-H H...A D...A D-H...A
N1-H3N1...O2i 0.87 (3) 1.88 (3) 2.750 (2) 178 (3)
N1-H1N1...O3ii 0.91 (3) 1.91 (3) 2.780 (3) 158 (2)
N1-H2N1...O3i 0.89 (3) 2.06 (3) 2.930 (3) 167 (2)
N1-H4N1...O3iii 0.92 (3) 1.86 (3) 2.777 (2) 173 (3)
N2-H4N2...O2 0.92 (3) 2.00 (3) 2.910 (2) 174 (2)
N2-H2N2...O2i 0.89 (3) 1.93 (3) 2.809 (2) 174 (2)
N2-H1N2...O4 0.83 (3) 2.02 (3) 2.840 (2) 171 (3)
N2-H3N2...O4iv 0.85 (3) 1.95 (3) 2.793 (2) 176 (3)
O1-H1O...O4v 0.73 (3) 1.89 (3) 2.613 (2) 171 (4)
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+1; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ATOMS (Dowty, 2006)[Dowty, E. (2006). ATOMS. Shape Software, Kingsport, Tennessee, USA.]; software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).


Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB6976 ).


Acknowledgements

The X-ray centre of the Vienna University of Technology is acknowledged for providing access to the single-crystal diffractometer.

References

Bruker (2009). APEX2, SAINT and SADABS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.
Dowty, E. (2006). ATOMS. Shape Software, Kingsport, Tennessee, USA.
Khan, A. A., Roux, J. P. & James, W. J. (1972). Acta Cryst. B28, 2065-2069.  [CrossRef] [ChemPort] [details]
Khan, A. A., Straumanis, E. & James, W. J. (1970). Acta Cryst. B26, 1889-1892.  [CrossRef] [ChemPort] [details] [ISI]
Kunz, P. C., Wetzel, C. & Spingler, B. (2010). Acta Cryst. E66, i26-i27.  [CrossRef] [details]
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.  [CrossRef] [details]
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.  [ISI] [CrossRef] [ChemPort] [details]


Acta Cryst (2012). E68, i82  [ doi:10.1107/S1600536812043565 ]

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