TITLE:
High Electrical Conductivity and Conspicuous Phase Transitions in Single Crystals of K-TCNQ
AUTHORS:
Yadunath Singh
KEYWORDS:
Electrical Conductivity, Radical Ion Salt, Tetracyanoquinodimethane, Charge Density Wave, Charge Transfer Complexes, A Semiconductor to a Metal Phase Transition
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.7 No.11,
November
30,
2017
ABSTRACT: This paper is to report the temperature dependent electrical conductivity of single crystals of radical ion salt (RIS) potassium-TCNQ (K-tetracyanoquino- dimethane) in a wide range of temperatures from 30 to 500 K. This RIS is quasi-one-dimensional in nature. These single crystals of K-TCNQ are grown by different methods like electrochemical, solution growth and diffusion method. Activation energy is determined for the sample in different temperature regions and found different values. More than one semiconductor to metal phase transition is observed in the studied samples during electrical measurements below and above room temperature. All the features observed in the studied samples are analyzed in the framework of their molecular structure as well as under different effects like disorder, impurity, Coulomb interaction, charge density wave (CDW), scattering and 3-D effects etc.