We report the preparation, crystallization, and solid-state characterization of the first member of a new family of tris(1,9-disubstituted phenalenyl)silicon neutral radicals. In the solid state, the radical packs as weak partial pi-dimers with intermolecular carbon center dot center dot center dot carbon contacts that fall at the van der Waals atomic separation. Magnetic susceptibility measurements indicate similar to 0.7 Curie spins per molecule from room temperature down to 50 K, below which antiferromagnetic coupling becomes apparent; the compound has a room-temperature single-crystal conductivity Of sigma(RT) = 2.4 x 10(-6) S cm(-1).