In music, a septimal diatonic semitone (or major diatonic semitoneHaluska, Jan (2003). The Mathematical Theory of Tone Systems, p.xxiv & 25. .) is the interval 15:14 . It is about 119.44 cents. The septimal diatonic semitone may be derived from the harmonic series as the interval between the fourteenth and fifteenth harmonics (B7b and B).
