If the carbon atom is surround by atoms with a higher electronegativity, its charge becomes more positive. The first peak of the carbon distribution, containing the most electronegative carbons, contains mostly of methyl groups. These carbons carry a negative charge as they are bounded to the positively charged hydrogen atoms. The carbon atom that is a part of the second peak is a carbon atom bound to two hydrogen atoms, and two carbon atoms. This makes it less electronegative than a methyl group as the carbon atoms are less positive than hydrogen atoms, but the carbon is still fairly negatively charged as true electronegative atoms are absent in its direct chemical environment. When an oxygen atom is introduced, we see that the carbon atom becomes less negatively charged as indicated by peak 3. This tendency becomes even stronger when the carbon atom is bonded to two electronegative atoms (peak 5). In addition, Fig. shows that not only the sp3 distribution of carbon atoms becomes more resolved, but that this effect is also observed for the sp-hybridized carbon atoms.