dft study and comparison between b6c4si and c16 clusters as a vitamin c carrier

in this study the chemical properties of b6c4si and c16 clusters connected vitamin c have been investigated using density functional theory (dft). nmr parameters and homo- lumo gap energy are calculated by using density functional method (b3lyp) with 6-311g* basis set. calculations show that homo- lumo gap energy of vitamin c decreases after connecting to b6c4si or c16 cluster decreasing of homo- lumo gap energy, causes that vitamin c can act better as an electron donor and antioxidant. the nmr results show that vitamin c connects stronger to b6c4si cluster in negative charges than positive charge. thus by creating a negative field, vitamin c can be connected to the b6c4si cluster and delivered easily by a positive filed. but for c16 cluster, the nmr results are quite different.