An electronically excited dimer, 'non-bonding' in the @G02704@. For example, a complex formed by the interaction of an excited @M03986@ with a @G02704@ partner of the same structure.
See also:
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1114 [Terms] [Paper]
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2240 [Terms] [Paper]