Variation of chemical shielding with intermolecular interactions and rovibrational motion. II. 15N and 13C nuclei in NNO and CO2

In the gas phase, the chemical shielding of a nucleus in terms of temperature and density can be written in a virial expansion, σ (T,ρ) =σ0(T)+σ1(T) ρ+σ2(T) ρ2+⋅⋅⋅. σ0(T) and σ1(T) functions have been determined for 13C in CO2 and both 15N nuclei in NNO. As expected, the terminal 15N has the largest chemical shift. The results are compared with data for other systems such as 1H, 19F, 31P, and 129Xe.