Previous work has implied the formation of 'condensed complexes' of cholest
erol and phospholipids in monolayers at the air-water interface. The presen
t study gives illustrative theoretical calculations of phase diagrams, conc
entration profiles, and average molecular areas when more than one complex
is assumed to be present. It is shown that multiple complexes should be det
ectable experimentally under some but not all conditions. The relationship
between condensed complexes in monolayers and bilayers is discussed. (C) 20
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