Crystal Quality of Naphtacene Single Crystals Obtained by Physical Vapor Transport Method

The crystal quality of naphtacene single crystals obtained by the physical vapor transport method using a horizontally arranged furnace has been examined by morphological investigation, the Laue method, and diffractometry. Using the physical vapor transport method, two types of single crystals were obtained: large plateletlike crystals and small three-dimensional (3D) crystals. The experimental results of the morphological investigation and diffractometry suggest that both types of crystal are of possess high quality; however, the result for the Laue method suggests that large platelet-like crystals are of possess excellent quality and that small crystals are of inferior quality. It appears that small crystals cannot grow futher size because they include a large strain.