From islamqa.com:
Question:
Husband and wife were quarreling because of the second wife. in anger during the fight he held her head and hit it on the wall. she went into coma and never recovered until she died. Is he doomed, or will he be saved by intention.
Answer:
What the husband did, holding his wife’s head and hitting it against the wall, is an evil act and is not permissible, because Allaah has not permitted striking the wife in this manner. Rather there is a concession allowing hitting her to discipline her, after exhorting her and forsaking her in bed, on the basis that it should not be a painful blow, and should not leave a mark or break a bone, and it should not be done with motives of revenge or to express one’s anger. [...]
