The ii^o7, v^o7, and vi^o7 embellishing diminished seventh chords are used in major keys only.

ii^o7 embellishes the tonic

The diminished seventh chord built on the raised 2^nd scale degree, ii^o7, embellishes I and its inversions.

v^o7 embellishes the subdominant

The diminished seventh chord built on the raised 5^th scale degree, v^o7, embellishes IV and its inversions.

vi^o7 embellishes the dominant

The diminished seventh chord built on the raised 6^th scale degree, vi^o7, embellishes V and V⁷ and their inversions.

The embellishing diminished seventh chords do not resolve in the regular way to their expected “tonics.”

Review: Regular resolutions of diminished seventh chords

Embellishing resolutions

Note that the unresolved diminished 7^ths of ii^o7 (do), v^o7 (fa), and vi^o7 (so) are the roots of the embellished I, IV, and V⁽⁷⁾ chords. The remaining three notes of the diminished seventh chord resolve to the nearest chord tone, but the diminished 7^th of the chords remain unresolved as common tones. At times the embellishing resolution sounds like a deceptive treatment of the dissonant 7^th.

Voice Leading

1. The ii^o7 embellishing the tonic triad and its inversions

Note how the embellishing diminished seventh chord occurs as a result of neighbor tones, appoggiaturas, and passing tones.

Incomplete triadic variants

In the first two examples below, the doubled roots of the tonic chord are kept, with the neighboring tones implying an incomplete ii^o7. In the third example, the neighboring group provides all four notes of the diminished seventh chord. These incomplete triadic examples show the early development of the embellishing diminished seventh chords as double neighbor tones.

2. The vi^o7 embellishing the dominant triad and dominant seventh chord, and their inversions

3. The v^o7 embellishing the subdominant triad and its inversions