Electronic structure of metal hydrides and amorphous materials II

Despite the simplest possible electronic structure of hydrogen, tremendous complexity can arise when it participates in the formation of solids. We have predicted crystal structures of metal hydrides under pressure and utilized the stochastic quenching method to understand the role that hydrogen can play in affecting electronic properties of certain amorphous materials.

We have predicted crystal structures of metal hydrides under pressure to study structural transformation and phenomena such as metallization which allows us to model metallic hydrogen and associated high-temperature superconductivity. Furthermore, very fundamental aspects of hydrogen in metals have been investigated by us, shedding light on the interplay between interstitial sites occupation and lattice strain. Most recently, we have also utilized the stochastic quenching method to improve our understanding of certain amorphous materials and the role that hydrogen can play in affecting their electronic properties.

References

  1. “A new probe of the electronic structure of Amorphous materials”, M. Strømme, R. Ahuja and G. A. Niklasson, Phys. Rev. Lett. 93 206403 (2004).

  2. “Cubic metallic phase of aluminum hydride showing improved hydrogen desorption”, R. H. Scheicher, D. Y. Kim, S. Lebègue, B. Arnaud, M. Alouani, and R. Ahuja, Applied Physics Letters 92, 201903 (2008).

  3. “Crystal structure of the pressure-induced metallic phase of SiH4 from ab initio theory”, D. Y. Kim, R. H. Scheicher, S. Lebègue, J. Prasongkit, B. Arnaud, M. Alouani, and R. Ahuja, Proceedings of the National Academy of Sciences of the USA 105, 16454 (2008).

  4. “Predicted High-Temperature Superconducting State in the Hydrogen-Dense Transition- Metal Hydride YH3 at 40 K and 17.7 GPa”, D. Y. Kim, R. H. Scheicher, and R. Ahuja, Physical Review Letters 103, 077002 (2009).

  5. “General trend for pressurized superconducting hydrogen-dense materials”, D. Y. Kim, R. H. Scheicher, H.-K. Mao, T. W. Kang, and R. Ahuja, Proceedings of the National Academy of Sciences of the USA 107, 2793 (2010).

  6. “Predicted Formation of Superconducting Platinum-Hydride Crystals under Pressure in the Presence of Molecular Hydrogen”, D. Y. Kim, R. H. Scheicher, C. J. Pickard, R. J. Needs, and R. Ahuja, Physical Review Letters 107, 117002 (2011).

  7. “Unveiling the complex electronic structure of amorphous metal oxides”, C. Århammar, A. Pietzsch , N. Bock , E. Holmström , C.M. Araujo , J. Gråsjö , S. Zhao , S. Green , T. Peery , F. Hennies , S. Amerioun , A. Föhlisch , J. Schlappa , T. Schmitt , V. N. Strocov, G. A. Niklasson , D. C. Wallace , J.E. Rubensson , B. Johansson and R. Ahuja, PNAS (the Proceedings of the National Academy of Sciences, USA) 108, 6355 (2011).

  8. “Atomic Diffusion in Solid Molecular Hydrogen”, A. B. Belonoshko, M. Ramzan, H. K. Mao and R. Ahuja, Nature-Scientific Reports 3, 2340 (2013).

  9. “Effect of uniaxial strain on the site occupancy of hydrogen in vanadium from density- functional calculations”, R. Johansson, R. Ahuja, O. Eriksson, B. Hjörvarsson, and R. H. Scheicher, Scientific Reports 5, 10301 (2015).

  10. “Structural characterization of amorphous Fe(1-x)Zrx”, R. Johansson, G. Muscas, S. George, M. Ahlberg, K. Kádas, D. Arvanitis, R. Ahuja, O. Eriksson, R. H. Scheicher and P. Jönsson, in manuscript.