[2] He was born in Split, Yugoslavia, and acquired a music grounding from his grandfather, the composer Josip Hatze.
In addition he attended classes in Siena, Paris and Darmstadt, given by Vito Frazzi, René Leibowitz, Olivier Messiaen, György Ligeti, Pierre Boulez and Henri Pousseur.
[3][6] As a composer, Radica's early style was essentially neo-classical; in the Grove Dictionary of Music and Musicians, Nikša Gligo instances the compositions in Četiri dramatska epigrama (Four Dramatic Epigrams, 1959), and the Concerto abbreviato (1960).
[7] Gligo comments that some of Radica's later works, with a focus on the relation between speech patterns and "motivic musical ideas", have a style reminiscent of Janáček and early Stravinsky.
[3] Radica's works included several ballet/dance scores, large-scale orchestral pieces, chamber and choral music and songs, and an opera, Prazor (The Dawn, 1991).