standard thermodynamic quantities

Values of thermodynamic functions in the standard state characterized by a standard pressure, molality or amount concentration, but not by temperature. Standard quantities are denoted by adding the superscript or to the symbol of the quantity. PAC, 1994, 66, 533 (Standard quantities in chemical thermodynamics. Fugacities, activities and equilibrium constants for pure and mixed phases (IUPAC Recommendations 1994)) on page 536