Investigation of the nature of the unpaired electron states in the organic semiconductor N-methyl-N-ethylmorpholinium-tetracyanoquinodimethane
Investigation of the nature of the unpaired electron states in the organic semiconductor N-methyl-N-ethylmorpholinium-tetracyanoquinodimethane
复制标题
有机半导体N-甲基-N-乙基吗啉鎓-四氰基醌二甲烷中不成对电子态性质的研究
DOI：
10.1103/physrevb.21.3437
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发表时间：
1980
影响因子：
3.7
通讯作者：
C. S. Jacobsen
中科院分区：
文献类型：
--
作者：
M. Rice;V. Yartsev;C. S. Jacobsen
采用偏振光反射测量和微观理论分析相结合的方法，研究了结晶有机半导体N-methyl-N-ethylmorpholinium-tetracyanoquinodimethane[MEM(TCNQ)2]二聚相中未成对电子态的性质。结果表明，每个未成对电子定域在一个二聚体TCNQ单元上，并证明了容纳未成对电子的两位分子轨道(MO)涉及二聚体单元的内部分子扭曲。推导了传统分子π分子轨道跃迁积分、分子振动频率和线性电子-分子-振动耦合常数的实验值，以及稍不等价的分子轨道能量差.首次观察到与未成对电子与π分子的高频伸缩模式耦合极弱有关的二聚体电荷振荡.
The nature of the unpaired electron states in the dimerized phase of the crystalline organic semiconductor N-methyl-N-ethylmorpholinium-tetracyanoquinodimethane [MEM (TCNQ) 2] is investigated by the combined means of polarized-optical-reflectance measurements and microscopic theoretical analysis. It is found that each unpaired electron is localized on a dimeric TCNQ unit, and it is demonstrated that the two-site molecular orbital (MO) which accommodates the unpaired electron involves internal molecular distortion of the dimeric unit. Experimental values are deduced for the intradimer π MO hopping integral, the TCNQ monomer a g molecular-vibration frequencies and linear-electron-molecular-vibration coupling constants, and the difference in energy of the slightly nonequivalent TCNQ monomer π MO's. The dimer charge oscillation associated with the extremely weak coupling of the unpaired electron to the high-frequency a g CH stretch mode of the TCNQ molecule is observed for the first time.