ðɪ ɛntˈaɪɚ mˈɛkənˌɪzəm ɪz ʌnsˈɜːʔn̩ pˈɑːɹtli bɪkˈʌz ˌɪntɚmˈiːdiət stˈeɪts ɑːɹ nˌɑːt ˈɔːlweɪz stˈeɪbəl ɪnˈʌf fɔːɹ stˈʌdi, ænd pˈɑːɹʃəli bɪkˈʌz ɡˈɑː bˌiːˈɑːɹ θɹˈiː ɪz stˈʌdid lˈɛs fɹˈiːkwəntli ðɐn ɡˈɑː sˌiːˈɛl θɹˈiː.
The entire mechanism is uncertain partly because intermediate states are not always stable enough for study, and partially because GaBr3 is studied less frequently than GaCl3.