frequency, f,ν

Reciprocal of the period.
Source:
Green Book, 2nd ed., p. 11
See also:
frequency in photochemistry
PAC, 1996, 68, 957 (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 974
PAC, 1996, 68, 2223 (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2244