Although only about 1 out of 100 carbon atoms in a naturally occurring organic molecule is the 13 C isotope, chemists are often able to synthesize molecules that are artificially enriched in 13 C at s...Although only about 1 out of 100 carbon atoms in a naturally occurring organic molecule is the 13 C isotope, chemists are often able to synthesize molecules that are artificially enriched in 13 C at specific carbon positions, sometimes to the point where the 13 C isotope is incorporated at a given position in over half of the molecules in the sample.