Is it permissible to give expiation for an oath in money to orphans, or must it only be in food to the poor, as stipulated by Islamic law?

You are required to offer expiation (kaffara) for breaking an oath, because you have refrained from an action (working) that involves boycotting and estrangement. The expiation for an oath is not feeding sixty poor people; rather, it is one of four things: feeding ten poor people, or clothing ten poor people, or freeing a slave. These three are given as choices. If you are unable to do all of them, then you must fast for three days. The proof for this is the saying of the Prophet, peace and blessings be upon him: "Whoever swears an oath, then sees something better than it, let him do that which is better and expiate for his oath." And the Almighty's saying: "Allah will not impose blame upon you for what is unintentional in your oaths, but He will impose blame upon you for what you intended of oaths. So its expiation is the feeding of ten poor people from the average of that which you feed your [own] families or clothing them or the freeing of a slave. But whoever finds not [the means] - then a fast of three days. That is the expiation for your oaths when you have sworn. And guard your oaths. Thus does Allah make clear to you His verses that you may be grateful."