Substantial compliance with donor-imposed formal requirement

(a) A powerholder's substantial compliance with a formal requirement of appointment imposed by the donor, including a requirement that the instrument exercising the power of appointment make reference or specific reference to the power, is sufficient if: (1) The powerholder knows of and intends to exercise the power; and (2) The powerholder's manner of attempted exercise of the power does not impair a material purpose of the donor in imposing the requirement.