The Prophet ﷺ said regarding a man who has intercourse with his wife while she is menstruating, "He should give a Dinar or half a Dinar in charity."
حدثنا مسدد حدثنا يحيى عن شعبة حدثني الحكم عن عبد الحميد بن عبد الرحمن عن مقسم
عن النبي ﷺ في الذي يأتي امرأته وهي حائض قال يتصدق بدينار أو نصف دينار
[Sahih] Ibn Majah narrated it in "Purification," chapter on the atonement for one who has intercourse with a menstruating woman, no. 640, from the hadith of Yahya Qattan, through this route. There are two other chains for it in Tirmidhi, no. 136, 137. See the coming hadith no. 266. As for the hadith of Abu Dawud, Hakim graded it sahih (1/171, 172), and Dhahabi agreed with him.