The assessed phase diagram of Ti-C system in Fig. 1 is taken from [1998Oka]. Other recent assessments of this system were done by [1995Alb], [1996Jon1], and [1996Sei]. The system consists of two terminal solids aTi and bTi and bTi and a refractory monocarbide TiC. The phase Ti2C does not appear in the equilibriam phase diagram, as there appears to be a tendency of carbon ordering at the stoichiometry. Other phases present are liquid and graphite (C). Two eutectic and one peritectoid reaction appear in this system at 1646, 2776, and 920 °C, respectively

Abstract

Ab initio electronic-structure calculations are performed using density functional theory (DFT) with polarized basis set (LanL2DZ and 6-311G++) within the spin polarized generalized gradient approximation for lithium intercalated graphite. Initially different benzene-Li+ model clusters are optimized on the basis of their total energy at room temperature. These model clusters are used to calculate the optimized structure of lithium intercalated graphite clusters. The resultant optimized structures are used to calculate dipole moment, ionization potential (IP), electron affinity (EA), binding energy (BE) and vibrational spectra (IR and Raman). For an idea of the band gap of the clusters in the ground state, the HOMO-LUMO gap (ΔEg) has been calculated. To compare the electron transfer ability of different clusters, chemical potential (μ), hardness (η) and their ratio for different clusters have also been determined.