The present investigation concerns the solid-state nuclear magnetic resonance spectroscopy of the 31P spin pair in the novel three-membered heterocyclic compound 3-(dichloromethylene)-trans-1,2-bis(2,4,6-tri-tert-butylphenyl)- 1,2-diphosphirane using the magic-angle-spinning (MAS) technique. The homogeneous 31P lineshapes are analyzed to extract the principal components of the shielding tensors using the Maricq and Waugh description of homonuclear spin-pair systems by average-Hamiltonian theory, modified to encompass the n = 0 rotational resonance situation. The experimental values of the shielding-tensor components are compared with those obtained from ab initio calculations performed on the model molecule P2C2H4 to aid further the interpretation of the 31P MAS NMR spectrum of the chloromethylene-diphosphirane. The magnitudes and orientations of calculated shielding-tensor components of the model compound methylene-diphosphirane P2C2H4 are compared with those for the phosphorus spin pair in the molecular environments of P2, P2H2, and P2H4. The electronic structures and bonding in all of those molecular species are discussed.
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