[MеnCpM(CO)3]-Na+ containing n= 0,1,3-5 anions of Cr, Mo and W have been synthesized and e investigated by 1H and 13C NMR method.Dependence of screening of magnetic atom nucleus on alkylating degree determined and the existence of “vicinal” effect, formed at 1.7-1.8 m.p. quantity between methyl groups in cyclopenthadienyl ring identified.