A @F02366@ bounded by two different bulk phases. When the bulk phases are identical the @F02366@ is described as symmetric.
Source: PAC, 1994, 66, 1667. (Thin films including layers: terminology in relation to their preparation and characterization (IUPAC Recommendations 1994)) on page 1671 [Terms] [Paper]
Cite as: IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). Online version (2019-) created by S. J. Chalk. ISBN 0-9678550-9-8. https://doi.org/10.1351/goldbook.