A new generation of double pyridazine molecular rotors differing in intramolecular dipole–dipole spacing was synthesized. All rotor molecules formed bulk inclusions in a tris(o-phenylenedioxy)cyclotriphosphazene (TPP) host. Results of dielectric spectroscopy were fitted to a pair of nine-state models that accounted for interactions of neighboring dipoles at either an aligned or opposed possible orientation
合成了分子内偶极-偶极间距不同的新一代双
哒嗪分子转子。所有转子分子在三(o-苯二氧基)环三
磷腈(
TPP)主体。介电谱的结果被拟合到一对九态模型,该模型解释了在
TPP主体通道内局部三倍偶极子旋转势的对准或相对可能取向下相邻偶极子的相互作用。结果表明,偶极子与偶极子之间的相互作用强度在100到200 K的范围内,导致偶极子优先填充低能构型的子集。他们还发现,在3和6位带有
乙炔基取代基的
哒嗪具有比带有1个
乙炔基和1个叔丁基的那些更高的旋转势垒(3.2–3.5 kcal / mol)。丁基(1.9–3.0 kcal / mol)。冷却后,这些势垒极大地降低了势阱之间的热转变速率,以至于夹杂物无法达到有序的偶极基态。