Rights: © 2005 American Physical Society (APS). This is the accepted version of the following article: Ma, Yuchen & Foster, A. S. & Krasheninnikov, A. V. & Nieminen, Risto M. 2005. Nitrogen in graphite and carbon nanotubes: Magnetism and mobility. Physical Review B. Volume 72, Issue 20. 205416/1-6. ISSN 1550-235X (electronic). DOI: 10.1103/physrevb.72.205416, which has been published in final form at http://journals.aps.org/prb/abstract/10.1103/PhysRevB.72.205416.