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Correlation and Dimerization Effects on the Physical Behavior of the $NR_4 [Ni(dmit)_2]_2$ Charge Transfer Salts : A DMRG Study of the Quarter-Filling t-J Model

Marie-Liesse Doublet·Marie-Bernadette Lepetit
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Abstract

The present work studies the quasi one-dimensional $Ni(dmit)_2$-based compounds within a correlated model. More specifically, we focus our attention on the composed influence of the electronic dimerization-factor and the repulsion, on the transport properties and the localization of the electronic density in the ground-state. Those properties are studied through the computation of the charge gaps (difference between the ionization potential and the electro-affinity: IP-EA) and the long- and short-bond orders of an infinite quarter-filled chain within a $t-J(t,U)$ model. The comparison between the computed gaps and the experimental activation energy of the semiconductor $NH_2Me_2 [Ni(dmit)_2]_2$ allows us to estimate the on-site electronic repulsion of the $Ni(dmit)_2$ molecule to $1.16eV$.

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Marie-Liesse Doublet, Marie-Bernadette Lepetit. 1998-09-30. Correlation and Dimerization Effects on the Physical Behavior of the $NR_4 [Ni(dmit)_2]_2$ Charge Transfer Salts : A DMRG Study of the Quarter-Filling t-J Model. https://doi.org/10.1063/1.477884

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