Spin—Rotation Interaction and Magnetic Shielding in OF2

Abstract

High‐resolution microwave spectroscopy has been used to study the spin—rotation interaction of the two ¹⁹F nuclei in OF₂. Several transitions were resolved from J=9 to J=26 where half‐widths at half‐heights of 12–15 kc/sec were obtained. The chemical shift of the ¹⁹F nucleus was also measured. The value of the magnetic shielding relative to F in CFCl₃ is −249±1 ppm. The paramagnetic component of the shielding in OF₂(σOF₂^p) is then related to the paramagnetic shielding in F₂(σF₂^p) yielding σOF₂^p—σF₂^p=205×10⁻⁶. σF₂^p can be computed from the known spin—rotation constant in F₂ yielding σOF₂^p=−569×10⁻⁶. This data is then combined with the microwave data on the spin—rotation interaction in OF₂ to yield M_aa=−42kc/sec, M_bb=−22 kc/sec, and M_cc=−49 kc/sec.