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Low-Temperature Transitions of Some Ammonium Salts

Published online by Cambridge University Press:  06 March 2019

M. Stammler ,
D. Orcutt  and
P. C. Colodny
M. Stammler
Affiliation:
Aerojet-General Corporation Sacramento, California
D. Orcutt
Affiliation:
Aerojet-General Corporation Sacramento, California
P. C. Colodny
Affiliation:
Aerojet-General Corporation Sacramento, California
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Abstract

X-ray diffraction studies were performed on ammonium fluoroborate [NH4BF4], ammonium perchlorate [NH4ClO4], ammonium chloride [NH4CI] and ammonium phosphate [(NH4)H2PO4] within a temperature range of ambient to −190°C. For these experiments a specimen holder was designed to effect rapid cooling of the sample. Results indicate that the fluorob orate and perchlorate salts undergo a polymorphic transition at −190°C. The decreasing intensities of the (011) and (112) reflections of the orthorhombic modification indicates a firstorder reaction. No transition was observed when these salts were cooled to −40°C. The ammonium chloride shows a transition at about −30°C which confirms the results obtained by G. H. Goldschmidt and D. G. Hurst. The ammonium phosphate (NH4)H2PO4, which is tetragonal at ambient temperature also undergoes a transition if cooled to −190°C. The kinetics of this reaction are discussed.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 6: Eleventh Annual Conference on Applications of X-ray Analysis, August 8-10, 1962 , 1962 , pp. 202 - 209
Copyright
Copyright © International Centre for Diffraction Data 1962

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References

1. Ketedaar, J. A., Nature 134: 250, 1934.Google Scholar
2. Weigle, J. and Saini, H., Helv. Phys. Ada 9: 515, 1936.Google Scholar
3. Clusius, K., Kmis, A., and Schanzer, W., Z. anorg. Ckem. 236: 26, 1935.Google Scholar
4. Smits, A., Ketectaar, J. A., and Mailer, G. J., Z. phys. Chem. A75, 359, 1936.Google Scholar
5. Brown, R. N. and McLaren, A. C., Proc. Roy. Soc. (London) A: 239, 1962.Google Scholar
6. Erofeev, E. V. and Mitskevich, N. I.,J. Phys. Chem. USSR 24: 1235, 1950; 26: 848, 1631. 1952; 27: 118, 1953.Google Scholar
7. Wcltman, H. J., “Low Temperature X-ray Diffraction of Frozen Electrolytes,” Advances in X-ray Analysis, Vol. 5, University of Denver, Plenum Press, New York, 1962, pp. 48–56.Google Scholar
8. Goldschmidt, G. H. and Hurst, D. G., Phys. Rev. 83: 88, 1951.Google Scholar