A metal complex represented by the following formula (1-b): wherein M represents an iridium atom or a platinum atom, n 1 represents 1, 2 or 3, n 2 represents 0, 1 or 2, and n 1 +n 2 is 3 when M is an iridium atom, while n 1 +n 2 is 2 when M is a platinum atom, E 2 and E 3 represent a nitrogen atom, and E 4 represents a carbon atom, and R 2 and R 3 may be either present or not present, R 2 and R 3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and when a plurality of R 2 and R 3 are present, they may be the same or different at each occurrence, R 4, R 5, R 6 and R 7 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and when a plurality of R 4, R 5, R 6 and R 7 are present, they may be the same or different at each occurrence, and R 4 and R 5 may be combined together to form a ring together with the carbon atoms to which they are attached, R 5 and R 6 may be combined together to form a ring together with the carbon atoms to which they are attached, and R 6 and R 7 may be combined together to form a ring together with the carbon atoms to which they are attached, R 8, R 10 and R 12 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and R 9 and R 11 each independently represent an alkyl group and this alkyl group optionally has a substituent, and when a plurality of R 8, R 9, R 10, R 11 and R 12 are present, they may be the same or different at each occurrence, the ring B represents a triazole ring, and A 1 -G 1 -A 2 represents an anionic bidentate ligand, A 1 and A 2 each independently represent a carbon atom, an oxygen atom or a nitrogen atom and these atoms each may be an atom constituting a ring, G 1 represents a single bond or an atomic group constituting the bidentate ligand together with A 1 and A 2, and when a plurality of A 1 -G 1 -A 2 are present, they may be the same or different. M represents an iridium atom or a platinum atom, n 1 represents 1, 2 or 3, n 2 represents 0, 1 or 2, and n 1 +n 2 is 3 when M is an iridium atom, while n 1 +n 2 is 2 when M is a platinum atom, E 2 and E 3 represent a nitrogen atom, and E 4 represents a carbon atom, and R 2 and R 3 may be either present or not present, R 2 and R 3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and when a plurality of R 2 and R 3 are present, they may be the same or different at each occurrence, R 4, R 5, R 6 and R 7 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and when a plurality of R 4, R 5, R 6 and R 7 are present, they may be the same or different at each occurrence, and R 4 and R 5 may be combined together to form a ring together with the carbon atoms to which they are attached, R 5 and R 6 may be combined together to form a ring together with the carbon atoms to which they are attached, and R 6 and R 7 may be combined together to form a ring together with the carbon atoms to which they are attached, R 8, R 10 and R 12 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a halogen atom and these groups each optionally have a substituent, and R 9 and R 11 each independently represent an alkyl group and this alkyl group optionally has a substituent, and when a plurality of R 8, R 9, R 10, R 11 and R 12 are present, they may be the same or different at each occurrence, the ring B represents a triazole ring, and A 1 -G 1 -A 2 represents an anionic bidentate ligand, A 1 and A 2 each independently represent a carbon atom, an oxygen atom or a nitrogen atom and these atoms each may be an atom constituting a ring, G 1 represents a single bond or an atomic group constituting the bidentate ligand together with A 1 and A 2, and when a plurality of A 1 -G 1 -A 2 are present, they may be the same or different.