each occurrence of subscripts d, m, n, o and p independently is an integer wherein d is from 2 to 6 in a first embodiment, 2 or 3 in a second embodiment and 2 in a third embodiment; m is 0 to 20; n is 0 to 18; o is 0 to 20; and, p is 0 to 20, with the proviso that m+n+o+p is equal to or greater than 2.