Dynamic Mechanical Behaviour of Organic Molecular Crystals. I

Abstract
The forced resonance vibration method was applied to several needle-like organic crystals, triphenylene (I), 1,2,3,4-dibenzanthracene (II), coronene (III), anthracene-trinitrobenzene (TNB) complex (IV), perylene-TNB (V), coronene-TNB (VI), acridine-iode (VII), and acetyl-acetone-Gu (VIII), and their elastic constants were obtained. The observed Young’s moduli, E1 of these organic crystals were E1(I)=1.19×1010 dyn/cm2, E1(II)=2.81×1010, E1(III)=1.10×1010, E1(IV)=1.24×1011(V)=7.77×1010, E1(VI)=9.99×1010, E1(VII)=1.67×1011 and E1(VIII)=2.87×1010 dyn/cm2. These values are consistent with the E1-values of some aromatic hydrocarbons, as obtained from the acoustic velocity.