1. Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study (NZIAS), Massey University Albany, Private Bag 102904, Auckland 0745, New Zealand
2. School of Natural and Computational Sciences, Massey University Albany, Private Bag 102904, Auckland 0745, New Zealand
3. Department of Physics, University of Auckland, Auckland, New Zealand
4. Department of Physics, The MacDiarmid Institute for Advanced Materials and Nanotechnology, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
5. Centre for Theoretical Chemistry and Physics, School of Natural and Mathematical Sciences, Massey University Albany, Private Bag 102904, Auckland 0745, New Zealand
6. Centre for Advanced Study (CAS) at the Norwegian Academy of Science and Letters, Drammensveien 78, NO-0271 Oslo, Norway