A minor seventh flat five chord, also known as a half diminished seventh chord, is composed using a root/1st, minor 3rd, diminished 5th and minor 7th (or R/1-♭3-♭5-♭7) intervals played simultaneously. Generally written as Cmi7(♭5), C∅ or C-7(-5), it is good practice to simply use an uppercase C with lowercase letters mi followed by a superscripted 7(♭5) to represent it in writing (ie: Cmi7(♭5)).
The minor seventh flat five chord is built upon the seventh degree of the harmonized major scale (tetrads) and possesses an extraordinary drive towards root resolution. The tonality of a minor seventh flat five chord is dissonant, unstable and unresolved.
Minor seventh flat five chord profile
|Intervals||root/1st, minor 3rd, diminished 5th, minor 7th or R/1-♭3-♭5-♭7|
|Stability||Dissonant, unstable, unresolved|
|Common names (examples in C)||Cmi7(♭5), C∅, C−7(-5), Half Diminished|
Minor seventh flat five chord table
|Chord name||Root||Minor third||Diminished fifth||Minor seventh|
|D♭mi7(♭5)||D♭||F♭ (E)||A (G)||C♭ (B)|
|G♭mi7(♭5)||G♭||B (A)||D (C)||F♭ (E)|
|A♭mi7(♭5)||A♭||C♭ (B)||E (D)||G♭|
|C Minor seventh flat five chord voicing #2|