What is the legal ruling for someone who swore by divorce, saying: "It is unlawful and a divorce that I will not give a single riyal until you take a certain thing from my brother," and then they did not take that thing, so he broke his oath and paid the money? Does this count as a divorce, or does it require expiation, and if it is expiation, what is its amount?

The oath using the word "haram" is among the unexplicitphrases that depend on the intention of the one swearing. If you intended divorce by it, then you have issued two divorces. If you intended ẓihār (a pre-Islamic form of divorce by likening one's wife to an unmarriageable relative), or if you did not intend anything, then you are bound by divorce and ẓihār. You can take back your wife during her 'iddah (waiting period) without a new contract if intercourse occurred and this was not the third divorce. As for ẓihār, it is not permissible for you to have intercourse with her until after expiation, and expiation is not obligatory until you return (to the prohibited act).