Calculations of 19F NMR shieldings in polyfluoro-1-lithioethenes: Role of geometry, solvation and comparison with experimental shifts

19F NMR chemical shielding constants in (E)-1,2-difluoroethenyllithium (1) and trifluoroethenyllithium (2) have been calculated by the SOS-DFPT-IGLO1For explanation of acronym SOS-DFPT-IGLO see Section 4. od and employed for an assignment of individual signals in experimental 19F NMR spectra of polyfluoro-1-lithioethenes. The role of solvation on equilibrium geometries and consequently on the shielding constants is discussed. In comparison to HF2Acronym HF stands here for computations at the Hartree–Fock level, acronym MP2 for computations including correlation using second-order Møller–Plesset correction, acronym DFT for computations using Density Functional Theory. P2 methods, DFT calculated absolute shielding values for fluoroalkenes differ from the experimental values by an opposite offset error. All methods gave acceptable relative shielding values.