Does a divorce take effect when a man says to his wife, "You are divorced," speaking aloud to himself, without her hearing him?

Allah does not hold a servant accountable for what they merely think to themselves, as long as they do not act upon it or speak of it. Therefore, if someone intends to divorce his wife but does not utter it, the divorce does not take effect. Similarly, if someone promises to divorce (his wife) if such-and-such happens or if his wife does such-and-such, the divorce does not take effect unless he actualizes it and pronounces it.