Does divorce take effect if the fiancé utters the phrase "upon me be what is unlawful" without intending divorce, and as a result of a state of anger, knowing that he had previously said "if you want this, it will be yours" in response to his fiancée's request for divorce, without remembering whether he had sworn by divorce or not?

A husband's statement to his wife, "If you want this, it shall be," is merely a promise and does not constitute divorce, especially if he did not intend divorce. Similarly, a husband's statement, "I declare it unlawful upon myself" (عليّ الحرام), does not constitute divorce if he did not intend divorce. The definitive statement in divorce is that of the husband, as he is most knowledgeable of his own intention.