Investigation of Magnetic Shielding in Xenon Difluoride Using Solid-State NMR Spectroscopy and Relativistic Density Functional Theory

The xenon and fluorine magnetic shielding tensors, σ, of XeF2 are characterized using solid-state 129Xe and 19F NMR spectroscopy and nonrelativistic and spin−orbit relativistic zeroth-order regular approximation density functional theory (ZORA DFT). Analysis of 129Xe and 19F NMR spectra acquired with magic-angle spinning at several spinning rates indicates that the Xe and F magnetic shielding tensors are axially symmetric, as dictated by the crystal symmetry. The isotropic 129Xe chemical shift is −1603 ± 5 ppm with respect to OXeF4 (neat liquid, 24 °C) and the Xe magnetic shielding anisotropy, Ω, is 4245 ± 20 ppm, the first anisotropy measured directly for a xenon compound. The parallel component of the experimentally determined xenon chemical shift tensor, δ∥ = −4433 ppm differs from δ(Xe(free atom)) by ∼1000 ppm, providing the first experimental demonstration that relativistic effects play an important role in the nuclear magnetic shielding for xenon. Both the sign and magnitude of the isotropic indirec...