We have used the pulse-radiolysis time-resolved microwave conductivity technique (PR-TRMC) to study the charge transport properties of the free-radical sandwich complex bis(octakis(dodecyloxy)phthalocyaninato) lutetium(III), [(C12O)(8)Pc](2)Lu. This compound displays multimesomorphic thermotropic behavior with two columnar liquid crystalline phases, D-x and D-h, between the freshly precipitated crystalline solid at room temperature, K-v, and the isotropic liquid, I, at 196 degrees C. In contrast with all other discotic materials previously studied using the PR-TRMC technique, the mobility of charge carriers is found to increase markedly at the transition from the K-v phase to the first columnar mesophase, D-x. The mobility displays a further substantial increase on entering the higher temperature hexagonal columnar phase, D-h. The intracolumnar mobility determined just above the D-x --> D-h transition temperature of 90 degrees C is 0.17 x 10(-4) m(2)/(V s), which is the highest yet determined for a columnar liquid crystalline material. The decay kinetics of the mobile charge carriers show a complex dependence on temperature with a first half-life that increases by orders of magnitude at the K --> D-x and D-x --> D-h transitions. The results are discussed in terms of both intramolecular and intermolecular structural changes.