Is the divorce of an angry person, who told his wife, "You are divorced," with the intention of scaring and deterring her, valid?

If divorce is written in a message without being uttered, and the intention was to threaten and annoy, not to effectuate divorce, then the preponderant view is that it does not take place. It is advised to live together amicably and to beware of anger, for it is the key to evil, and the Prophet, peace and blessings be upon him, repeatedly advised against anger.