nmr and nbo calculation of broccoli calm: nano physical parameter study

sulforaphane, an isothiocyanate found in broccoli and other cruciferous vegetables. it is an antioxidantand anti-cancer agent, and reduces blood pressure, and also has anti-allergic effects.in this article, six theoretical methods have been used for calculation of physical parameters insolforaphane and several similar compounds. we calculated physical parameters like atomic charges.energy (ae) , chemical shift anisotropy (5) , asymmetry parameter (t) , chemical shift anisotropy(an) , dipole moment , isotropic , anisotropic , nmr determinant and distance matrix determinant,and in this work we used gaussian 98 at nmr and natural bond orbital( nbo) calculation by usinghf method with 6-31g,6-31g* and 6-31+g basis set and b3lyp , blyp and b3pw9 i methodswith 6-31g basis set. the ciao magnetic shielding for studied molecules was obtained by usinggauss view program. chemical shift curve was drawn for all of the atoms in each molecular.