TY  - JOUR
A1  - Lindic, Tilen
A1  - Sinha, Shreya
A1  - Mattsson, Stefan
A1  - Paulus, Beate
T1  - Prediction of a model crystal structure for Ni2F5 by first-principles calculations
JF  - Zeitschrift für Naturforschung : B, Chemical sciences
N2  - Electrochemical fluorination in anhydrous HF, also known as the Simons process, is a widely used industrial method for fluorination of organic compounds. Its mechanism, being not so well understood, has long been debated and is believed to involve higher valent nickel fluorides formed on the nickel-plated anode during the process. One of these is speculated to be Ni2F5, which was previously reported in the literature and assigned via infrared spectroscopy, but its crystal structure is not yet known. We have identified known crystal structures of compounds with similar stoichiometries as Ni2F5 and utilized them as a starting point for our periodic DFT investigations, applying the PBE+U method. Ni2F5 as the most stable polymorph was found to be of the same crystal structure as another mixed valent fluoride, Cr2F5. The calculated lattice parameters are a = 7.24 angstrom, b = 7.40 angstrom, c = 7.08 angstrom and beta = 118.9 degrees with an antiferromagnetic ordering of the nickel magnetic moments.
KW  - crystal structure prediction
KW  - DFT
KW  - Ni2F5
Y1  - 2022
U6  - https://doi.org/10.1515/znb-2022-0072
SN  - 0932-0776
SN  - 1865-7117
VL  - 77
IS  - 6
SP  - 469
EP  - 473
PB  - De Gruyter
CY  - Berlin
ER  -