Magnetic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>3</mml:mn><mml:mi>d</mml:mi></mml:mrow></mml:math> adatoms on free-standing and Ni(111)-supported graphene

We present an extensive density functional theory analysis of the structural, electronic, and magnetic properties isolated $3d$ transition metal adatoms (from Ti to Co) adsorbed on free-standing Ni(111)-supported graphene. discuss how energetics different adsorption sites is influenced by filling $d$-orbital across series identify a direct correlation between adatom-graphene distance degree charge transfer. The presence Ni substrate found have stronger impact at end series, leading modifications preferred site, transfer, spin properties. exchange coupling adatom magnetization changes as function both in sign (preferred antiferromagnetic for Ti, V, Cr, ferromagnetic alignment other elements) magnitude 90 meV Mn $\ensuremath{\approx}10$ Fe Co).