Half diminished scale
||I, II, III, IV, V, VI, VII
|C, D, E♭, F, G♭, A♭, B♭, C
|Number of pitch classes
The half diminished scale is a musical scale more commonly known as "Locrian ♮2", name which avoids confusion with the diminished scales (see octatonic scales) and the half-diminished seventh chord (min. 7, flat 5). It may be considered Mode VI, the sixth mode, of the ascending melodic minor scale. See: jazz scale.
On C the scale is associated with dmi7♭5, which functions as a iio chord in minor. See: chord-scale system.
Locrian ♮2 is commonly used in jazz and some rock. It is commonly practiced by such neoclassical metal guitarists Michael Romeo, and such jazz pianists as Oscar Peterson and Jonah Cristall-Clarke.
The half diminished scales, although derived from classical scales, offer fresh potentials in harmonic and melodic structure.