Energy band and conductivity of (PyH) [Ni(dmit)2]2

As theoretical approach for synthesized molecular conductor (PyH) [Ni(dmit)(2)](2) two-dimensional energy bands have been calculated by using EHMO tight binding method. Intermolecular HOMO-HOMO overlap integrals of various [Ni(dmit)(2)](-0.5) (...) [Ni(dmit)(2)](-0.5) pairs in the two-dimensional conductive network have also been calculated. The calculated energy gap 0.17 eV is in accord with the measured conducting activation energy 0.15 eV, indicating that (PyH) [Ni(dmit)(2)](2) is a semiconductor with the narrow energy gap. Based on energy band calculation, the structure-properties correlations have been discussed. Among various structural factors, the uniformity and the compactibility of the array of the [Ni(dmit)(2)](-0.5) play a crucial part in influencing the conductivity of the (PyH) [Ni(dmit)(2)](2) crystal.