Aluminum atom van der Waals complexes of the form Al-(N-2)(x) and Al-(CO2)(x) are prepared in a molecular beam environment using a laser vaporization pulsed nozzle cluster source. These species are studied with threshold laser photoionization in a time-of-flight mass spectrometer. Ionization thresholds as a function of cluster size reveal cluster bonding energetics and evidence for intracomplex reactions. The ionization potential of Al-N-2 (5.805 eV) is combined with the dissociation energy of Al+-N-2 to yield the bond energy (466 cm(-1)) of the Al-N-2 van der Waals complex. In the Al-(CO2)(x) system, the intracluster metal oxidation reaction proceeds spontaneously only after "solvation" by at least five CO2 molecules. The ionization threshold red shift indicates that D-0(Al+-CO2) greater than or equal to 2453 cm(-1).