|Budget Amount *help
¥7,200,000 (Direct Cost : ¥7,200,000)
Fiscal Year 1994 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1993 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1992 : ¥6,000,000 (Direct Cost : ¥6,000,000)
It is very important to obtain big and good quality crystals of organic charge transfer complexes for study of their physical properties. The purpose of this study is to obtain big and good quality crystals of organic charge transfer complexes.
We offered the concept that in electrocrystallization of charge-transfer complexes, the current applied on the both electrodes must be controlled so that this is directly proportional to the surface area of the growing crystal in order to obtain good quality crystals with no uncontrolled nucleations of new crystals or defects. According to the concept, below formula of relation between applied current and period of crystal growth could be derived :
where I is applied current (muA) , t is period of crystal growth (day) . According to this formula, crystal growth was carried out in 60ml of suitable organic solvent dissolved organic donor 0.13mmol, supporting electrolyte 0.52mmol with applied current from 0.1 to 4muA at 20ﾟC under N_2 gas. By this preparation, good quality crystals of (TMTTF) _2Br, (TMTSF) _2X (X=C10_4, PF_6 and AsF_6) and (BEDT-TTF) _2X (X=Cu (SCN) _2, Cu [N (CN) _2] -Cl, Cu [N (CN) _2] Br and KHg (SCN) _4) were obtained. In general, their crystals had flatter surface than the ones obtained by the usual method with constant applied current, and the shape of the crystals were bulky.
We believe firmly that the concept is very useful for crystal growth of organic materials in solvent. In the near future, we will use the concept for crystal growth of charge transfer complexes by diffusion method, condensation method and recrstalization.