Luminescent janus-type, two-coordinated metal complexes

A compound of Formula III or Formula IV:

• wherein E is a carbene coordinated to metal M, wherein E has the structure:
• each E can be the same or different;
• each ring D is independently a single or fused carbocyclic ring or heterocyclic ring, which may be saturated or unsaturated, which is bound covalently bound to Z, wherein each ring D may be the same or different, and wherein each ring D is independently substituted with R;
• Z is a linking group selected from the group consisting of a single bond, aryl, heteroaryl, alkyl, O, S, NR, and combinations thereof;
• m is 2, 3, or 4;
• G is a single or fused heterocyclic ring, which may be saturated or unsaturated;
• which comprises m atoms Q;
• and which may be optionally substituted with one or more R,
• each occurrence of R and R′ is independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;
• each occurrence of Q is independently C or N;
• and
• M is Au, Ag, or Cu.