The present invention relates to a dinuclear molybdenum complex with ligands selected from fatty tertiary amines of formula (I): R—N[(CH2)nR2][(CH2)nR3]  (I) wherein R represents a linear or branched alkyl comprising 3 to 30 carbon atoms, preferably 3 to 20, advantageously 7 to 17 carbon atoms; n, identical or different, represents 2 or 3; R2 and R3, identical or different, represent an O, OR, NR′2, COOR′, or COO group, where R′, identical or different, represents a hydrogen atom or an alkaline or alkaline earth metal, preferably R′ is H, preferably R2 and R3, identical or different, represent an OH or NH2 group.