C# Augmented (C#aug)
Also written as Db Augmented (Db and C# are the same key).
1+3+#5
Notes in C# Augmented
C# (root)E#A
Inversions
Same notes as C# Augmented, with a different chord tone as the lowest note. Useful for smoother movement between chords instead of jumping around the keyboard.
Root position
C# in the bass
1st inversion
E# in the bass
2nd inversion
A in the bass
The notes C#, E# and A make up C# Augmented.
Stretch the fifth of a major chord up by a semitone and the result is symmetrical: two identical major thirds stacked on top of each other. That symmetry means the chord has no clear sense of up or down, giving it a floating, slightly dizzying quality composers reach for when a moment needs to feel suspended or unresolved.