Disclosed is a transition metal complex represented by the following formula (1): (wherein: M represents a transition metal element; K represents an uncharged monodentate or bidentate ligand; L represents a monodentate or bidentate monoanionic or dianionic ligand; m and o represent an integer from 0 to 5; n represents an integer from 1 to 3; p represents an integer from 0 to 4; W— represents a counterion; and Y1 to Y4, R1, and R2 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocycloalkyl group, an aryl group, an aralkyl group, a heteroaryl group, an alkenyl group, an alkynyl group, or an alkoxy group).