Premium
Significant Reduction of On‐Site Coulomb Energy U due to Short‐Range Correlation in an Organic Mott Insulator
Author(s) -
Ohno Kaoru,
Noguchi Yoshifumi,
Yokoi Toshihiro,
Ishii Soh,
Takeda Jun,
Furuya Miou
Publication year - 2006
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.200600144
Subject(s) - coulomb , mott insulator , electron , spins , condensed matter physics , electric potential energy , electronic correlation , physics , wave function , interaction energy , coulomb barrier , intermolecular force , atomic physics , chemistry , quantum mechanics , energy (signal processing) , molecule
By carrying out a first‐principles T‐matrix calculation on multiple scatterings between electrons, we show that the intramolecular electron–electron interaction energy U , of a Mott insulator of the organic radical 1,3,5‐trithia‐2,4,6‐triazapentalenyl (TTTA) is significantly reduced from the naive expectation value of the Coulomb interaction (7.3 eV and 5.3 eV, respectively, for the bare and screened Coulomb interactions) to 2.9 eV due to the short‐range correlation. This result together with the intermolecular interaction energy D=1.3 eV explains the experimental optical gap (1.5 eV). The associated two‐particle wavefunction clearly shows the Coulomb hole indicating that two electrons with antiparallel spins cannot approach because of the Coulomb repulsion. We also discuss the energetics and magnetics of this system.