rational formula
In chemistry, a rational formula shows the arrangement of atoms in a molecule, often grouping functional groups together.
Rational formulas are used to explicitly show functional groups within a molecule.
構造式 (structural formula) provides a more detailed depiction of atomic connectivity and bonding than 示性式.
Compound of 示性 (shisei, 'indicating properties') and 式 (shiki, 'formula'). The exact historical derivation is uncertain; the term is a technical coinage in chemistry.