Abstract
A combination of 19F magic angle spinning (MAS) nuclear magnetic resonance (NMR) and density functional theory (DFT) were used to study the ordering of F atoms in Pb2Ti4O9F2. This analysis revealed that F atoms predominantly occupy two of the six available inequivalent sites in a ratio of 73 : 27. DFT-based calculations explained the preference of F occupation on these sites and quantitatively reproduced the experimental occupation ratio, independent of the choice of functional. We concluded that the Pb atom's 6s2 lone pair may play a role (∼0.1 eV per f.u.) in determining the majority and minority F occupation sites with partial density of states and crystal orbital Hamiltonian population analyses applied to the DFT wave functions.
| Original language | English |
|---|---|
| Journal | Dalton Transactions |
| DOIs | |
| State | Accepted/In press - 2022 |
Funding
The authors acknowledge Erica Heinrich for valuable help with manuscript preparation. The VESTA program53 was used to visualize the experimental and DFT crystal structures and electronic densities. The authors thank Prof. Sudo and Mr. Kitao of Kindai University for their help in the solid state NMR measurement. This work was partially supported by a Grant-in-Aid for Scientific Research on Innovative Area \u201CMixed Anion (Project JP17H05489, JP19H04706)\u201D (JSPS). The synchrotron radiation experiments were performed at the BL02B2 of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal No. 2016A1157 and 2018A1227). The ab initio calculations were performed with the computational resources of the Research Center for Advanced Computing Infrastructure (RCACI) at JAIST. The authors gratefully thank Division of Joint Research Center, Kindai University, for the solid-state NMR measurements. T. I. and F. A. R. acknowledge support from US Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. K. O. is grateful for financial support from Kansai Research Foundation for technology promotion and a Grant-in-Aids for Scientific Research (C) (Project JP16K05731 and 21K04659). K. H. is grateful for financial support from MEXT-KAKENHI (JP19K05029, JP21K03400, JP21H01998, and JP22H02170), and the Air Force Office of Scientific Research (Award Numbers: FA2386-20-1-4036). R. M. is grateful for financial supports from MEXT-KAKENHI (22H05146, 21K03400 and 19H04692), from the Air Force Office of Scientific Research (AFOSR-AOARD/FA2386-17-1-4049;FA2386-19-1-4015), and from JSPS Bilateral Joint Projects (JPJSBP120197714). This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( https://energy.gov/downloads/doe-public-access-plan ).