What is the expiation for a woman who swore falsely upon the Qur’an while she was menstruating?

Swearing by the Mus'haf or the Qur'an is a binding oath. It is permissible to swear by the Mus'haf using other wording, and this is considered an affirmation of the oath. A menstruating woman is not permitted to touch the Mus'haf, and she incurs sin if she does so. However, her menstruation does not affect her oath. If she swears falsely, she has committed one of the major sins, which is the "Al-Yamin Al-Ghamus" (the immersive oath), so named because it immerses its taker in the fire of Hell. Many scholars hold that it has no expiation other than repentance and seeking forgiveness. If she offers an expiation for an oath, that is more prudent.