1. EES-6 MS-T003, Los Alamos National Laboratory, Los Alamos, NM 87545, USA, Santa Fe Institute, Hyde Park Rd. 1399, Santa Fe, NM 87501, USA,
2. Department of Mathematical Sciences, NTNU, 7491 Trondheim, Norway
3. Theoretical Chemistry, University of Vienna, Austria
4. EES-6 MS-T003, Los Alamos National Laboratory, Los Alamos, NM 87545, USA