Theory of the a- and c-Axis Resistivity and Magnetoresistance in MoCl₅ Graphite Intercalation Compounds

The c-axis resistivity ρ_c and longitudinal magnetoresistance Δρ_cL/ρ₀ of MoCl₅ GIC's (stage-2 to 6) have been extensively studied theoretically in terms of the following series-resistance model: equation presented where n is the stage number, ρ_c(GIG) is the partial resistivity related to graphite-intercalant-graphite sandwich laver and _ρGG(i, i+1) corresponds to the resistivity associated with the i ↔ i+1 transition in an interior layer region without intervening intercalate layers. _ρGG(i, i + 1) makes a bottleneck in the conduction process along the c-axis, and plays an essential role in the longitudinal negative magnetoresistance for stage-4 to 6 and in the stage dependence of ρ_c vs. T curve. By using the same model we can explain the metallic temperature dependence and positive magnetoresistance in the in-plane conduction which is independent of the stage number.