The assembling of separate molecular entities into any aggregate, especially of oppositely charged free ions into ion pairs or larger and not necessarily well-defined clusters of ions held together by electrostatic attraction. The term signifies the reverse of dissociation, but is not commonly used for the formation of definite adducts by colligation or coordination.
[Source: PAC, 1994, 66, 1077 (Glossary of terms used in physical organic chemistry, IUPAC Recommendations 1994) on page 1086; http://goldbook.iupac.org/A00472.html]
09 - Chart Defining the different Chord Associations
14 - Chart with Symbols Defining the relative Simple and Compound Sympathetic Association
Law of Sympathetic Association
14.18 - Law of Sympathetic Association
15.15.05 - Progressive Association