On solitonic defects in hydrogen-bonded (HF)x Original Research Article

Results of first-principles, density-functional calculations on single, periodic chains of (HF)x are reported. The chains consist of repeated unit cells each containing four HF monomers and the structures are constructed such that they resemble periodically repeated solitonic (ionic or Bjerrum) defects. Special emphasisis put on exploring how experimental studies of the electronic properties are influenced by the presence of the solitons, i.e., whether experiments can demonstrate the presence of the solitons. It is found that studies of the electron density (in position or momentum space) are less convenient in this respect, whereas studies of the electronic single-particle energies may be used. Certain experimental techniques may also be able to distinguish between ionic and Bjerrum defects.