hexachloroantimonate. The intervalence charge-transfer (IVCT) band of 1(+) is narrow and asymmetric and exhibits only weak solvatochromism. Analysis of this band indicates that 1(+) is a class-III or class-II/III borderline mixed-valence species. In contrast, a broad, strongly solvatochromic IVCT band is observed for 2(+), indicating that this species is a class-II mixed-valence species. The assignment
(E)-4,4'-双[双(4-
甲氧基苯基)
氨基]
二苯乙烯,1,(E,E)-1,4-双[4-[双(4-
甲氧基苯基)
氨基]
苯乙烯基]苯, 2,和两个更长的同系物,(E,E,E)-4,4'-双[4-[双(4-
甲氧基苯基)
氨基]
苯乙烯基]
二苯乙烯,3和(E,E,E,E)- 1,4-双(4-[4-[双(4-
甲氧基苯基)
氨基]
苯乙烯基]
苯乙烯基)苯, 4, 已被三(4-
溴苯基) 六氯
锑酸盐氧化成单和二价。1(+) 的间隔电荷转移 (I
VCT) 带窄且不对称,仅表现出微弱的溶剂化变色。对该条带的分析表明 1(+) 是 III 类或 II/III 类临界混合价物种。相比之下,对于 2(+) 观察到一个宽的、强溶剂化变色的 I
VCT 带,表明该物种是 II 类混合价物种。将 1(+) 和 2(+) 指定为对称的 III 类和不对称的 II 类物种,
AM1 计算也支持。1(+) 和 2(+) 的 I
VCT 带的静寂分析给出了更大的电子耦合