Towards designing Mn4 molecules with strong intramolecular exchange coupling

Tóm tắt

Distorted cubane Mn4+Mn3+ 3 single-molecule magnets (SMMs) have been studied by first-principles calculations, i.e. [Mn4L3X(OAc)3(dbm)3] (L = O; X = F, Cl, and Br; dbmH = dibenzoyl-methane). It was shown in our previous paper (Tuan et al 2009 Phys. Chem. Chem. Phys. 11 717) that the ferrimagnetic structure of Mn4+Mn3+ 3 SMMs is dominated by π type hybridization between the dz 2 orbitals at the three high-spin Mn3+ ions and the t2g orbitals at the Mn4+ ion. To design new Mn4+Mn3+ 3 molecules having much more stable ferrimagnetic states, one approach is suggested. This involves controlling the Mn4+–L–Mn3+ exchange pathways by rational variations in ligands to strengthen the hybridization between the Mn ions. Based on this method, we succeed in designing new distorted cubane Mn4+Mn3+ 3 molecules having Mn4+–Mn3+ exchange coupling of about 3 times stronger than that of the synthesized Mn4+Mn3+ 3 molecules. These results give some hints regarding experimental efforts to synthesize new superior Mn4+Mn3+ 3 SMMs

Tài liệu tham khảo

[1] Bogani L and Wernsdorfer W 2008 Nat. Mater. 7 179

[2] Friedman J R, Sarachik M P, Tejada J and Ziolo R 1996 Phys. Rev. Lett. 76 3830 Thomas L, Lionti L, Ballou R, Gatteschi D, Sessoli R and Barbara B 1996 Nature 383 145

[3] Saitoh, Miyasaka H, Yamashita M and Clérac R 2007 J. Mater. Chem. 17 2002 Marvaud V, Herrera J M, Barilero T, Tuyeras F, Garde R, Scuiller A, Decroix C, Cantuel M and Desplanches C 2003 Monatshefte für Chem. 134 149 Milios C J, Vinslava A, Wernsdorfer W, Moggach S, Parsons S, Perlepes S P, Christou G and Brechin E K 2007 J. Am. Chem. Soc. 129 2754

[4] Inglis R, Taylor S M, Jones L F, Papaefstathiou G S, Perlepes S P, Datta S, Hill S, Wernsdorfer W and Brechin E K 2009 Dalton Trans. 42 9157 Ako A M, Mereacre V, Hewitt I J, Clérac R, Lecren L, Anson C E and Powell A K 2006 J. Mater. Chem. 16 2579

[5] Tuan N A, Katayama S and Chi D H 2009 Phys. Chem. Chem. Phys. 11 717

[6] Tuan N A, Katayama S and Chi D H 2008 Comput. Mater. Sci. 44 111 Han M J, Ozaki T and Yu J 2004 Phys. Rev. B 70 184421 Park K, Pederson M R, Richardson S L, Alcalde N A and Christou G 2003 Phys. Rev. B 68 020405 Park K, Pederson M R and Bernstein N 2004 J. Phys. Chem. Solids 65 805

[7] Bashkin J S, Chang H, Streib W E, Huffman J C, Hendricson D N and Christou G 1987 J. Am. Chem. Soc. 109 6502

[8] Wang S, Filting K, Streib W E, Schmitt E A, McCusker J K, Hendrickson D N and Christou G 1991 Angew. Chem., Int. Ed. Engl. 30 305

[9] Hendrickson N et al 1992 J. Am. Chem. Soc. 114 2455

[10] Li Q, Vincent J B, Libby E, Chang H, Huffman J C, Boyd P D W, Christou C and Hendrickson D N 1988 Angew. Chem., Int. Ed. Engl. 27 1731

[11] Wemple M W, Tsai H, Folting K, Hendrickson D N and Christou G 1993 Inorg. Chem. 32 2025

[12] Wang S, Tsai H, Libby E, Folting K, Streib W E, Hendrickson D N and Christou G 1996 Inorg. Chem. 35 7578

[13] Andres H, Basler R, Güdel H, Aromí G, Christou G, Büttner H and Rufflé B 2000 J. Am. Chem. Soc. 122 12469

[14] Aubin S M J, Dilley N R, Pardi L, Krzystek J, Wemple M W, Brunel L, Maple M B, Christou G and Hendrickson D N 1998 J. Am. Chem. Soc. 120 4991

[15] Wernsdorfer W, Aliaga-Alcalde N, Hendrickson D N and Christou G 2002 Nature 416 406

[16] Delley B 1990 J. Chem. Phys. 92 508

[17] Hammer B, Hansen L B and Norskov J K 1999 Phys. Rev. B 59 7413

[18] Delley B 1998 Int. J. Quantum Chem. 69 423

[19] Mulliken R S 1955 J. Chem. Phys. 23 1833 Mulliken R S 1955 J. Chem. Phys. 23 1841

[20] Sessoli R, Tsai H L, Schake A R, Wang S, Vincent J B, Folting K, Gatteschi D, Christou G and Hendrickson D N 1993 J. Am. Chem. Soc. 115 1804

[21] Yang C I, Wernsdorfer W, Lee G H and Tsai H L 2007 J. Am. Chem. Soc. 129 456

[22] Miyasaka H, Madanbashi T, Sugimoto K, Nakazawa Y, Wernsdorfer W, Sugiura K, Yamashita M, Coulon C and Clérac R 2006 Chem. Eur. J. 12 7028