Is it obligatory to give away the deceased father's used clothes as charity for others to benefit from them, or is it permissible to keep them to commemorate his memory?

Donating the deceased's clothes is preferable to keeping them, because charity given on behalf of the deceased is a form of righteousness that elevates their status with Allah. Moreover, donating them is more beneficial for both the deceased and the heir than keeping them merely for remembrance. It should be noted that these clothes have become the property of the heirs, so it is not permissible to dispose of them without their consent, unless you are the sole heir.