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Low- and high-temperature structures of neopentylglycol plastic crystal

Published online by Cambridge University Press:  10 January 2013

Dhanesh Chandra
Affiliation:
Department of Chemical and Metallurgical Engineering, Mackay School of Mines, University of Nevada, Reno, Nevada 89557
Cynthia S. Day
Affiliation:
Crystalytics Company, P.O. Box 82286, Lincoln, Nebraska 68501
Charles S. Barrett
Affiliation:
Department of Engineering, University of Denver, Denver, Colorado 80210

Abstract

Plastic crystals, such as neopentylglycol, 2, 2-dimethyl-1,3-propanediol, that exhibit polymorphic behavior are emerging materials for thermal energy storage. The energy is stored isothermally in the γ phase, FCC, during solid-state phase transformations. This γ phase of NPG has been determined as an orientational disordered phase. The low temperature α phase structure, which is of great significance in the evaluation of lattice expansions and other parameters, was first determined in 1961. However, the reported unit cell dimensions and the intensities of the reflections led to erroneous indexing of the powder patterns in binary systems. The α phase structure is redetermined here as monoclinic, M= 104.15 amu, space group P21/n (an alternate setting of , space group No. 14), a = 5.979(1)Å, b= 10.876(2)Å, c=10.099(2)Å, β=99.78(1)°, V=647.2(2)Å3 at 20°(± 1)C, Dx= 1.069 g cm s−3 for Z=4. In this paper the redetermined structure of the α phase of NPG is presented in projections of the atomic positions, in tables, and in calculated powder pattern and these results are compared with those reported by others. The powder patterns obtained from the Bragg–Brentano diffractometer are compared with our calculated pattern from the single crystal data. The structural parameters of the high temperature phase of NPG as determined by a Guinier diffraction system are also reported.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1993

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References

Benson, D. K., Webb, J. D., Burrows, R. W., McFadden, J. D., and Christensen, C. (1986). Solar Energy Mater. 13, 133152.CrossRefGoogle Scholar
Chandra, D., Barrett, C. S., and Benson, D. K. (1986). Adv. X-Ray Anal. 29, 305313.Google Scholar
Chandra, D., Barrett, C. S., and Benson, D. K. (1989). Adv. X-ray Anal. 32, 609616.Google Scholar
Chandra, D., Lynch, R. A., Ding, W., and Tomlinson, J. J. (1990). Adv. X-ray Anal. 33, 445452.Google Scholar
Chandra, D., Fitzpatrick, J. J., and Jorgenson, G. (1985). Adv. X-Ray Anal. 28, 353360.Google Scholar
Chandra, D., Ding, W., Lynch, R. A., and Tomlinson, J. J., (1991). J. Less Common Metals 168, 159167.CrossRefGoogle Scholar
Frank, V. H. P., Krzemicki, K., and Voellenkle, H. (1973). Chem-Zig. 97(4), 206207.Google Scholar
Helms, J. H., Majumdar, A., and Chandra, D. (1992). J. Elec. Chem. Soc. (accepted paper).Google Scholar
Larson, A. C. (1967). Acta Cryst. 23, 664669.CrossRefGoogle Scholar
Llewellyn, F. J., Cox, E. G., and Goodwin, T. H. (1937). J. Chem. Soc. 883894.Google Scholar
Murrill, E., and Breed, L. (1970). Thermochemica Acta. 1, 239246.CrossRefGoogle Scholar
Murrill, E., and Breed, L. (1972). Thermochemica Acta. 3, 311315.CrossRefGoogle Scholar
Nakano, E., Hirotsu, K., and Shimada, A. (1969). Bull. Chem. Soc. Jap. 42, 3367.CrossRefGoogle Scholar
Nitta, I., and Watanabe, T. (1938). Bull Chem. Soc. Jap. 13, 2834.CrossRefGoogle Scholar
Smith, G. W. (1969). J. Chem. Phys. 50, 35953605.Google Scholar
Timmermann, J. (1961). J. Phyc. Chem. Solids 18(1), 18.CrossRefGoogle Scholar
Zannetti, R. (1961). Acta Cryst. 14, 203204.CrossRefGoogle Scholar