Crystal structure of α‐gutta percha: Modification of the constrained least‐squares method
- 1 February 1973
- journal article
- research article
- Published by Wiley in Journal of Polymer Science: Polymer Physics Edition
- Vol. 11 (2) , 233-248
- https://doi.org/10.1002/pol.1973.180110205
Abstract
The crystal structure of α‐gutta percha has been determined by x‐ray diffraction. The unit cell parameters are a = 7.98 Å, b = 6.29 Å, c (fiber period) = 8.77 Å, and β = 102.0° (monoclinic). The space group is P21/c–C2h5. Two molecular chains of nearly trans‐CTS‐trans‐CTS̄ conformation pass through a unit cell; C, T, S, and S̄ being the cis, trans, and two types of skew forms, respectively. The constrainedle astsquares method was modified so that the order of the least squares matrix could be reduced and was applied to the refinement of the crystal structure.Keywords
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