Stair Magnetism: Distinct Magnetic States of Co₅C₅ Carbide Isomers

Andrew Kuznetsov

ATG:biosynthetics, Merzhausen, Germany.

DOI: 10.4236/jmp.2013.43A061                

Abstract

Ruffle magnetic landscape of transition metals (TM) is a trouble of material science that makes it hard to predict properties of nanomagnets [1,2]. It is not quite clear, whether jumps in magnetic activity is the intrinsic property of TM complexes or a controversy of computational experiments. To solve this problem, isomers of Co₅C₅ carbide with various positions of carbon atoms on the vertices of Co₅ cluster were investigated in DFT (Density Functional Theory) computer simulations. It was found that magnetic moments of the carbide isomers increased with the decreasing number of Co–C bonds. However, C-2 isomers have three Co–C bonds demonstrated distinctive magnetic states. The Co₅C₅ carbide system showed a discrete magnetism. It was supposed that similar magnetic arrangements take place in endohedral metallofullerenes and filled nanotubes.

Keywords

The Metal Cluster; Carbon Shell; Magnetization; Emergence of Atypical Properties

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	I. Garg, H. Sharma, N. Kapila, K. Dharamvir and V. K. Jindal, “Transition Metal Induced Magnetism in Smaller Fullerenes (Cn for n ≤ 36),” Nanoscale, Vol. 3, No. 1, 2011, pp. 217-224. doi:10.1039/c0nr00475h
[2]	P. Tereshchuk and J. L. F. Da Silva, “Encapsulation of Small Magnetic Clusters in Fullerene Cages: A Density Functional Theory Investigation within van der Waals Corrections,” Physical Review B, Vol. 85, No. 19, 2012, Article ID: 195461. doi:10.1103/PhysRevB.85.195461
[3]	B. I. Swanson, S. I. Hamburg and R. R. Ryan, “Bonding in Divalent Transition Metal Cyanides. Crystal Structure of Dicesium Magnesium Hexacyanoferrate (II),” Inorganic Chemistry, Vol. 13, No. 7, 1974, pp 1685-1687. doi:10.1021/ic50137a028
[4]	E. A. Robinson, “Interpretation of Bond-Length Data for Transition-Metal-Acetylene Complexes, in Particular the Complex [C5H5NH][TaCI,(PhC=CPh)(NC5H5)],” Journal of the Chemical Society, Dalton Transactions, No. 12, 1981, pp. 2373-2375. doi:10.1039/dt9810002373
[5]	P. Susmita, Ch. Sayan, Ph. Manh-Huong, M. Pritish and S. Hariharan, “Carbon Nano Straws: Nanotubes Filled with Superparamagnetic Nanoparticles,” Nanotechnology, Vol. 20, No. 48, 2009, Article ID: 485604. doi:10.1088/0957-4484/20/48/485604
[6]	C. Soldano, F. Rossella, V. Bellani, S. Giudicatti and S. Kar, “Cobalt Nanocluster-Filled Carbon Nanotube Arrays: Engineered Photonic Bandgap and Optical Reflectivity,” ACS Nano, Vol. 4, No. 11, 2010, pp. 6573-6578. doi:10.1021/nn101801y
[7]	P. F. Weck, E. Kim, K. R. Czerwinski and D. Tomanek, “Structural and Magnetic Properties of Tcn@C60 Endohedral Metalofullerenes: First-Principles Predictions,” Physical Review B, Vol. 81, No. 12, 2010, Article ID: 125448.
[8]	M. B. Javan, N. Tajabor, M. Rezaee-Roknabadi and M. Behdani, “First Principles Study of Small Cobalt Clusters Encapsulated in C60 and C82 Spherical Nanocages,” Applied Surface Science, Vol. 257, No. 17, 2011, pp. 7586-7591. doi:10.1016/j.apsusc.2011.03.132
[9]	M. B. Javan and N. Tajabor, “Structural, Electronic and Magnetic Properties of Fen@C60 and Fen@C80 (n = 2 - 7) Endohedral Metallofullerene Nano-Cages: First Principles Study,” Journal of Magnetism and Magnetic Materials, Vol. 324, No. 1, 2012, pp. 52-59. doi:10.1016/j.jmmm.2011.07.034
[10]	P. L. Tereshchuk, “Energetic and Magnetic Properties of Chitosan with Embedded Co Clusters,” Computational Materials Science, Vol. 50, No. 3, 2011, pp. 991-997. doi:10.1016/j.commatsci.2010.10.038
[11]	A. Kuznetsov, “From Carbides to Co5 and Co13 Metallofullerenes: First-Principles Study and Design,” American Journal of Biomedical Engineering, Vol. 2, No. 1, 2012, pp. 32-38. doi:10.5923/j.ajbe.20120201.05
[12]	A. Kuznetsov, “Magnetic Properties of Endohedral Complexes Co5@Cn Depending upon the Size and Symmetry of Fullerenes as well as Orientation of Cobalt Cluster,” Computational Materials Science, Vol. 54, 2012, pp. 204- 207. doi:10.1016/j.commatsci.2011.09.034
[13]	M. D. Hanwell, D. E. Curtis, D. C. Lonie, T. Vandermeersch, E. Zurek and G. R. Hutchison, “Visualization, and Analysis Platform,” Journal of Cheminformatics, Vol. 4, 2012, pp. 1-17. http://www.jcheminf.com/content/4/1/17
[14]	P. Hohenberg and W. Kohn, “Inhomogeneous Electron Gas,” Physical Review B, Vol. 136, No. 3B, 1964, pp. B864-B871. doi:10.1103/PhysRev.136.B864
[15]	T. Ozaki, “Variationally Optimized Atomic Orbitals for Large-Scale Electronic Structures,” Physical Review B, Vol. 67, No. 15, 2003, Article ID: 155108. doi:10.1103/PhysRevB.67.155108
[16]	T. Ozaki and H. Kino, “Numerical Atomic Basis Orbitals from H to Kr,” Physical Review B, Vol. 69, No. 19, 2004, Article ID: 195113. doi:10.1103/PhysRevB.69.195113
[17]	T. Ozaki and H. Kino, “Efficient Projector Expansion for the ab Initio LCAO Method,” Physical Review B, Vol. 72, No. 4, 2005, Article ID: 045121. doi:10.1103/PhysRevB.72.045121
[18]	OpenMX, http://www.openmx-square.org/
[19]	P. Perdew, K. Burke and M. Ernzerhof, “Generalized Gradient Approximation Made Simple,” Physical Review Letters, Vol. 77, No. 18, 1996. pp. 3865-3868. doi:10.1103/PhysRevLett.77.3865
[20]	P. Császár and P. Pulay, “Geometry Optimization by Direct Inversion in the Iterative Subspace,” Journal of Molecular Structure, Vol. 114, 1984, pp. 31-34. doi:10.1016/S0022-2860(84)87198-7
[21]	http://www.jaist.ac.jp/~t-ozaki/vps_pao2006/vps_pao.html
[22]	G. Kresse and J. Hafner, “Ab Initio Molecular Dynamics for Open-Shell Transition Metals,” Physical Review B, Vol. 48, No. 17, 1993, pp. 13115-13118. doi:10.1103/PhysRevB.48.13115
[23]	G. Kresse and J. Furthmüller, “Efficient Iterative Schemes for ab Initio Total-Energy Calculations Using a Plane-Wave Basis Set,” Physical Review B, Vol. 54, No. 16, 1996, pp. 11169-11186. doi:10.1103/PhysRevB.54.11169
[24]	E. Blochl, “Projector Augmented-Wave Method,” Physical Review B, Vol. 50, No. 24, 1994, pp. 17953-17979. doi:10.1103/PhysRevB.50.17953
[25]	G. Kresse and D. Joubert, “From Ultrasoft Pseudopotentials to the Projector Augmented-Wave Method,” Physical Review B, Vol. 59, No. 3, 1999, pp. 1758-1775. doi:10.1103/PhysRevB.59.1758