Still here and working on part-writing. I have used a sharp ii dim7th chord, straight after iihalfdim7- leading to V. Is this actually the right place to put it in terms of chord sequence/harmonic progression? Obviously, as we are in minor, the ii chord is also dissonant, so the progression has to be treated very carefully.

I have voiced the two chords as follows. The key is E minor:

enter image description here

Potential issues:

1.As you can see, in the ii half dim7, I have an augmented 4th between the tenors and alto. This dissonance does not resolve in the next chord, and instead becomes another augmented 4th interval , just half a step up (C-Fsharp, Csharp-F double sharp). Is this acceptable/unavoidable?

  1. I have leapt into a dissonance from A to F sharp in the tenor (F sharp being the augmented 4th of the dissonance). Is this also unavoidable? (perhaps a remedy here is to double the E [5th] of the previous chord, allowing a move by step into the dissonance? although this would be unorthodox doubling).

Any help gratefully received!



  • #ii in key Em is a simple G note - which means it's diatonic, so why use Fx? – Tim Mar 27 at 14:37
  • @Tim ii in Em is F#, so #ii is Fx. G is iii in Em. The larger problem is that in standard theory there's no such thing as a #ii chord. It would be some kind of applied or common-tone chord. The progression here doesn't make harmonic sense -- at least not without additional context. – Aaron Mar 27 at 15:52
  • I agree. Knowing where the progression would/should go (and where it's coming from) would also be much more useful. – musicamante Mar 27 at 15:55
  • Maybe more to the point - why does OP want/need #ii? – Tim Mar 27 at 16:11
  • @Tim, I'm guessing it's homework. :D – Bennyboy1973 Mar 27 at 21:46

♯ii°7 is really only used for one of two reasons, and in both cases it will be labeled differently:

  1. As a vii°7/iii to tonicize iii. Notice that this really only works in major keys, because in minor the root of ♯ii is enharmonically equivalent to the root of III.

  2. As a common-tone diminished seventh (often labeled CT°7) expanding tonic.

Since you're in minor, the second option is really the only viable use of this chord, in which case you will typically go from i to this "♯ii°7" back to i. And since the purpose of the CT°7 is often to keep the common tone in the same voice, this "♯ii°7" will typically be in third inversion so that the bass E stays constant throughout.

For more on the common-tone diminished seventh, see the first half of this answer.

  • Well, in minor, it wouldn't be enharmonically equivalent to the root of the target chord as long as the Fxdim7 chord then tonicizes some kind of G# chord instead of G. Pretty unlikely, of course. – user45266 Mar 28 at 2:12
  • thanks for such a great answer Richard. I remember reading somewhere that sharp ii dim 7 can be used as a leading note dim 7th to V. This is actually how i was planning on using it here. (sharp ii dim 7-V). Do you have any knowledge of this function? – EdB123 Mar 28 at 17:00
  • 1
    @EdB123 Oh, interesting. In this case, that chord is best spelled with the raised fourth scale degree as root (a type of ♯iv°7 as opposed to ♯ii°7). This is enharmonic to ♯ii°7, but it's important to spell it with ♯iv as the root to show its function as a leading-tone chord resolving to V. That definitely happens, but I would say it comes after IV far more often than after ii. – Richard Mar 28 at 17:06

You've discovered one of the tricks that Romantic piano music is based on-- throw layers and layers of dim7 chords one after the other, especially during your flashy crashy-bangy solo sections, and you'll get a dramatic sound that can end up on any key you want.

A fundamental rule in music is that raised tones rise. An augmented F wants to resolve a half-step up: to G#. I'd recommend g# minor, since it's going to be pretty easy to get to B7 and back to e.

One comment as a music teacher: write more NEATLY. Get a thick mechanical pencil (0.5mm is good) with a soft lead. And frame your page properly, because not doing so shows disrespect to the people whom you would like help from.

  • This comment sets a pretty high bar, so maybe it should not end with a preposition. – Areel Xocha Mar 27 at 23:04
  • You think that was the kind of comment up with which the OP should not put? :D – Bennyboy1973 Mar 27 at 23:06
  • Qui docet discit? – Areel Xocha Mar 27 at 23:23
  • That's my main reason for being here. There are quite a lot of smart cookies, here! – Bennyboy1973 Mar 27 at 23:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.