Did the divorce take effect on the wife if the husband swore to divorce her while angry, intending to intimidate her into telling the truth, and then discovered that she had lied about one question?

The relied-upon opinion is that suspending divorce upon a condition brings about divorce when the condition is met, whether the intent was to cause divorce or merely to threaten. So, if the wife lied after divorce was suspended upon her lying, then divorce occurs when the condition is met. It is permissible to take her back during the iddah (waiting period) unless this divorce completes the three divorces, and she returns [to the marital bond] simply by sexual intercourse. However, according to the opinion of Ibn Taymiyyah, divorce does not occur; rather, an expiation for an oath (kaffarat yamin) becomes due. It is obligatory to be cautious about swearing by divorce.