| Title: |
Core level spectroscopies locate hydrogen in the proton transfer pathway – identifying quasi-symmetrical hydrogen bonds in the solid state |
| Authors: |
Stevens, JS; Coultas, S; Jaye, C; Fischer, DA; Schroeder, SLM |
| Publisher Information: |
Royal Society of Chemistry |
| Publication Year: |
2020 |
| Collection: |
White Rose Research Online (Universities of Leeds, Sheffield & York) |
| Description: |
Short, strong hydrogen bonds (SSHBs) have been a source of interest and considerable speculation over recent years, culminating with those where hydrogen resides around the midpoint between the donor and acceptor atoms, leading to quasi-covalent nature. We demonstrate that X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy provide deep insight into the electronic structure of the short OHN hydrogen bond of 3,5-pyridinedicarboxylic acid, revealing for the first time distinctive spectroscopic identifiers for these quasi-symmetrical hydrogen bonds. An intermediate nitrogen (core level) chemical shift occurs for the almost centrally located hydrogen compared to protonated (ionic) and non-ionic analogues, and it reveals the absence of two-site disorder. This type of bonding is also evident through broadening of the nitrogen 1s photoemission and 1s → 1π* peaks in XPS and NEXAFS, respectively, arising from the femtosecond lifetimes of hydrogen in the potential wells slightly offset to either side of the centre. The line-shape of the core level excitations are thus related to the population occupancies, reflecting the temperature-dependent shape of the hydrogen potential energy well. Both XPS and NEXAFS provide a distinctive identifier for these quasi-symmetrical hydrogen bonds, paving the way for detailed studies into their prevalence and potentially unique physical and chemical properties. |
| Document Type: |
article in journal/newspaper |
| File Description: |
text |
| Language: |
English |
| ISSN: |
1463-9076 |
| Relation: |
https://eprints.whiterose.ac.uk/id/eprint/157789/1/c9cp05677g.pdf; Stevens, JS, Coultas, S, Jaye, C et al. (2 more authors) (2020) Core level spectroscopies locate hydrogen in the proton transfer pathway – identifying quasi-symmetrical hydrogen bonds in the solid state. Physical Chemistry Chemical Physics (9). pp. 4916-4923. ISSN: 1463-9076 |
| Availability: |
https://eprints.whiterose.ac.uk/id/eprint/157789/; https://eprints.whiterose.ac.uk/id/eprint/157789/1/c9cp05677g.pdf |
| Rights: |
cc_by_3 |
| Accession Number: |
edsbas.C51F010C |
| Database: |
BASE |