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Updated: Jun 23, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Packing structures and periodic band calculations on DPO (2,5-dipicryl-1,3,4-oxadiazole)
Gui-xiang Wang1, Chun-hong Shi, Xue-dong Gong
1Department of Chemistry, Computation Institute for Molecules and Materials, Nanjing University of Science and Technology, Nanjing 210094, China.
Abstract:
Molecular mechanics (MM) method with Compass and Dreiding force fields is used to predict molecular packing for DPO among the 7 most possible space groups (P2(1)/c, P-1, P2(1)2(1)2(1), P2(1), Pbca, C2/c, and Pna2(1)), respectively. Then, periodic band calculations are performed on the predicted crystals using the DFT-GGA-RPBE method. Obtained density of state (DOS) shows that C-O, CN-O(2) and N-N bonds are possibly the trigger bond during thermolysis. Band gap (DeltaE(g)) equals 1.33 eV, which shows DPO with higher sensitivity. Periodic calculation results are consistent well with that drawn from bond dissociation energy calculations on gas molecule.
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