The present invention provides a complex compound, etc., which has superior
moisture- and heat-resistances, etc. and is used for an
optical recording medium, including: a compound represented by Formula (I) below [in the formula, R1 represents an
alkyl group which may have one or more substituents, etc., R2 represents a cyano group, etc., R3 represents an
alkyl group which may have one or more substituents, etc., R4 represents a
hydrogen atom, etc., R5 represents Formula (III) (in the formula, the ring A represents a heterocycle which may have one or more substituents, wherein the heterocycle is any one selected from a
pyrimidine ring, a
tetrazole ring, etc.)]; a
metal; and any one
ion selected from the group consisting of an
ion formed by addition of one or more protons to an amine, an
ammonium ion and a
quaternary ammonium ion.