Density functional theory investigation of3dtransition metal NMR shielding tensors in diamagnetic systems using the gauge-including projector augmented-wave method

Abstract

We present a density functional theory based method for calculating NMR shielding tensors for 3d transition metal nuclei using periodic boundary conditions. Calculations

Practical aspects of 51V and 93Nb solid-state NMR spectroscopy and applications to oxide materials

“…Most recently an ultrasoft pseudopotential (USPP) modification of the GIPAW method has been applied to systematically calculate 49 Ti and 51 V shielding parameters in a series of molecular and extended periodic systems [143]. Thirteen different vanadate compounds, with total of 18 distinct vanadium sites, were computed, and a very good correlation was found between theoretical and experimental values of isotropic chemical shift.…”

Density Functional Theory Calculations of 95Mo NMR Parameters in Solid‐State Compounds

“…Since it is well known that the nature and quality of the USPP can affect the precision of the results, [80] the influence of different parameters has been evaluated even if the results shown above, where the standard Mo PP is considered, are satisfactory. As previously mentioned in the literature, two projectors per momentum channel is efficient to properly calculate NMR properties, so no further investigation was performed.…”

“…As previously mentioned in the literature, two projectors per momentum channel is efficient to properly calculate NMR properties, so no further investigation was performed. [54,80] Variation of the PP cut-off radii was first considered. As our standard PP is already quite soft, the atomic energy convergence cut-off being about 400 eV, only smaller radii have been considered.…”

“…[73][74][75][76][77][78] Recently, the first application to 3d transition metals has been performed for V and Ti. [79,80] To study large systems containing heavier transition metals, such as molybdenum, the PAW and GIPAW methods have to be tested as they have never been applied to the calculation of core properties of 4d elements. The significant number of core electrons as well as the highly localised 4d electrons questions the relevance of the PP approximation.…”

Electric field gradient calculations in paramagnetic compounds using the PAW approach. Application to 23Na NMR in layered vanadium phosphates

“…[21] Valence-core interactions were described using ultra-soft pseudopotentials (USPP) generated by the OTF USPP generator of CASTEP 4.4. CASTEP default USPP were used for all atoms except for vanadium for which we employed the USPP previously described by Truflandier et al [22] Calculations of EFG parameters were performed using a PAW reconstruction of valence wave functions allowing an all-electron precision within the pseudopotential formalism of CASTEP. A convergence of ±0.01 MHz and ±0.01 was achieved for 23 Na C Q and η Q parameters, respectively, using a plane wave energy cut-off of 600 eV.…”