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 as Yngwie Malmsteen and 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.