Sanibel Symposium

Single-molecule magnetic complex [Mn₁₂O₁₂(O₂CH)₁₆(H₂O)₄] has twelve Mn atoms. Four of them forms the core [Mn₄ ⁴⁺O₄] surrounded by the ring of eight Mn³⁺. The core’s Mn atoms have three electrons on 3d-oribitals with total spin of S=3/2, and the interaction between four Mn atoms of the core is ferromagnetic forming total spin of the core S=6. The eight remaining Mn atoms are in 3+ charge state with four electrons on d-orbital with total spin of S=2 forming total spin of the Mn₈ ring of S=16. The magnetic interaction between the Mn₄ core and the Mn₈ ring is antiferromagnetic. Thus the ground state of the complex has total spin state S=10. Here we present the ground state configuration for all-electron local orbital (aeLO) DFT calculations in comparison with pseudopotential plane waves (PPPW) calculations. The significant difference between aeLO and PPPW structures is the formation of additional hydrogen bonds with H₂O molecules to the nearest O atoms of the core. These second H-bonds cause the additional distortion of the Mn₈ ring of the complex.