Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
harmonize [ˈhɑːmənaɪz] vi (MUS) гармони́ровать (impf) (colours, ideas)
to harmonize (with) гармони́ровать (impf) (с +instr)
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.