Ab-initio calculations of the Fe4N hyperfine parameters pressure dependence

A.V. GIL REBAZA, J. DESIMONI, E. PELTZER Y BLANCÁ, S. COTTENIER

VIENNA, AUSTRIA

Conferencia; ICAME09; 2009

AB-INITIO CALCULATIONS OF THE Fe4N HYPERFINE PARAMETERS PRESSURE DEPENDENCE4N HYPERFINE PARAMETERS PRESSURE DEPENDENCE A.V. Gil Rebaza1, J. Desimoni1,2, E. Peltzer y Blancá3 S. Cottenier4,5,61, J. Desimoni1,2, E. Peltzer y Blancá3 S. Cottenier4,5,6 1 Instituto de Física de La Plata, CCT-La Plata-CONICET, La Plata, Argentina.Instituto de Física de La Plata, CCT-La Plata-CONICET, La Plata, Argentina. 2 Departamento de Física, Facultad de Ciencias Exactas, UNLP, c.c. 67, 1900 La Plata – Argentina.Departamento de Física, Facultad de Ciencias Exactas, UNLP, c.c. 67, 1900 La Plata – Argentina. 3 Grupo de Estudio de Materiales y Dispositivos Electrónicos (GEMyDE), Facultad de Ingenieria, UNLP, CCT-La Plata, IFLYSIB-CONICET, c.c. 565, 1900 La Plata - Argentina.Grupo de Estudio de Materiales y Dispositivos Electrónicos (GEMyDE), Facultad de Ingenieria, UNLP, CCT-La Plata, IFLYSIB-CONICET, c.c. 565, 1900 La Plata - Argentina. 4 Computational Materials Engineering (CME), Institute for Minerals Engineering (GHI), Center for Computational Engineering Science (CCES) & Julich-Aachen Research Alliance (JARA), RWTH Aachen University, 52064 Aachen, Germany.Computational Materials Engineering (CME), Institute for Minerals Engineering (GHI), Center for Computational Engineering Science (CCES) & Julich-Aachen Research Alliance (JARA), RWTH Aachen University, 52064 Aachen, Germany. 5 Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium..Instituut voor Kern- en Stralingsfysica, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium.. 6 Center for Molecular Modeling, Ghent University, Proeftuinstraat 86, 9000 Ghent Belgium..Center for Molecular Modeling, Ghent University, Proeftuinstraat 86, 9000 Ghent Belgium.. Fe4N display a remarkably rich behaviour that has attracted the attention of applied as well as basic researchers for as long as 80 years. The earliest interest in the synthesis and study of Fe4N was motivated by its possible application as a catalyst for the production of ammonia and for its role in the surface treatment of steels with ammonia [1]. Later, its potential as a material for high-density magnetic recording was pointed out and was studied as a component in various thin film devices, due to its high magnetic flux density, low coercivity, low resistance and other suitable properties. This material has anti-perovskite structure with two distinguishable Fe atoms, an atom occupy the corners of the cubic unit cell, FeI, and the other in the face centre of cubic, FeII, while the N atoms is in the body centre [2]. We report ab-initio studies of the magnetic and hyperfine properties variations with pressure of both iron sites in the structure of Fe4N, using FP-LAPW [3-5] method and the Perdew-Burke-Ernzerhof functional of the Generalized Gradient Approximation [6] was used to describe the exchange-correlation potential. The results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII presents a discontinuity when the lattice parameter is varied. This is expressed mainly in the changes of the electronic structure and specifically in the behaviour of density of states, showing a compression of electronic states in the vicinity of -3eV. Furthermore, we show a good agreement between our calculations in the equilibrium and experimental data from Mossbauer [7] of the hyperfine field, isomer shift and the electric field gradient on the two iron sites. [1]. P.H. Emmett, S.B. Hendricks, S. Brunauer, Journal of the American Chemical Society 52, (1930) 1456. [2]. K.H. Jack, Proc. R. Soc. London A 208, 216 (1951). [3]. Sinsh D., Planewaves, Pseudopotentials and the LAPW Method, Kluwer Academic Publishers 1994. [4]. R.M. Martin, Electronic Structure, Basic Theory and Practical Methods, Cambridge University Press, 2004. [5]. P. Blaha, K. Schwarz, J. Luitz, G.K.H. Madsen, D. Kvasnicka, Wien2K, Technical University of Vienna, Vienna, Austria, 2001. [6]. J.P. Perdew, S. Burke and M. Ernserhof, Phys. Rev. Let. 77 (1996) 3865. [7]. E.L. Peltzer y Blancá, J. Desimoni, N.E. Christensen, H. Emmerich, S. Cottenier, Phys. Status Solidi B, 20 (2009)4N display a remarkably rich behaviour that has attracted the attention of applied as well as basic researchers for as long as 80 years. The earliest interest in the synthesis and study of Fe4N was motivated by its possible application as a catalyst for the production of ammonia and for its role in the surface treatment of steels with ammonia [1]. Later, its potential as a material for high-density magnetic recording was pointed out and was studied as a component in various thin film devices, due to its high magnetic flux density, low coercivity, low resistance and other suitable properties. This material has anti-perovskite structure with two distinguishable Fe atoms, an atom occupy the corners of the cubic unit cell, FeI, and the other in the face centre of cubic, FeII, while the N atoms is in the body centre [2]. We report ab-initio studies of the magnetic and hyperfine properties variations with pressure of both iron sites in the structure of Fe4N, using FP-LAPW [3-5] method and the Perdew-Burke-Ernzerhof functional of the Generalized Gradient Approximation [6] was used to describe the exchange-correlation potential. The results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII presents a discontinuity when the lattice parameter is varied. This is expressed mainly in the changes of the electronic structure and specifically in the behaviour of density of states, showing a compression of electronic states in the vicinity of -3eV. Furthermore, we show a good agreement between our calculations in the equilibrium and experimental data from Mossbauer [7] of the hyperfine field, isomer shift and the electric field gradient on the two iron sites. [1]. P.H. Emmett, S.B. Hendricks, S. Brunauer, Journal of the American Chemical Society 52, (1930) 1456. [2]. K.H. Jack, Proc. R. Soc. London A 208, 216 (1951). [3]. Sinsh D., Planewaves, Pseudopotentials and the LAPW Method, Kluwer Academic Publishers 1994. [4]. R.M. Martin, Electronic Structure, Basic Theory and Practical Methods, Cambridge University Press, 2004. [5]. P. Blaha, K. Schwarz, J. Luitz, G.K.H. Madsen, D. Kvasnicka, Wien2K, Technical University of Vienna, Vienna, Austria, 2001. [6]. J.P. Perdew, S. Burke and M. Ernserhof, Phys. Rev. Let. 77 (1996) 3865. [7]. E.L. Peltzer y Blancá, J. Desimoni, N.E. Christensen, H. Emmerich, S. Cottenier, Phys. Status Solidi B, 20 (2009)4N was motivated by its possible application as a catalyst for the production of ammonia and for its role in the surface treatment of steels with ammonia [1]. Later, its potential as a material for high-density magnetic recording was pointed out and was studied as a component in various thin film devices, due to its high magnetic flux density, low coercivity, low resistance and other suitable properties. This material has anti-perovskite structure with two distinguishable Fe atoms, an atom occupy the corners of the cubic unit cell, FeI, and the other in the face centre of cubic, FeII, while the N atoms is in the body centre [2]. We report ab-initio studies of the magnetic and hyperfine properties variations with pressure of both iron sites in the structure of Fe4N, using FP-LAPW [3-5] method and the Perdew-Burke-Ernzerhof functional of the Generalized Gradient Approximation [6] was used to describe the exchange-correlation potential. The results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII presents a discontinuity when the lattice parameter is varied. This is expressed mainly in the changes of the electronic structure and specifically in the behaviour of density of states, showing a compression of electronic states in the vicinity of -3eV. Furthermore, we show a good agreement between our calculations in the equilibrium and experimental data from Mossbauer [7] of the hyperfine field, isomer shift and the electric field gradient on the two iron sites. [1]. P.H. Emmett, S.B. Hendricks, S. Brunauer, Journal of the American Chemical Society 52, (1930) 1456. [2]. K.H. Jack, Proc. R. Soc. London A 208, 216 (1951). [3]. Sinsh D., Planewaves, Pseudopotentials and the LAPW Method, Kluwer Academic Publishers 1994. [4]. R.M. Martin, Electronic Structure, Basic Theory and Practical Methods, Cambridge University Press, 2004. [5]. P. Blaha, K. Schwarz, J. Luitz, G.K.H. Madsen, D. Kvasnicka, Wien2K, Technical University of Vienna, Vienna, Austria, 2001. [6]. J.P. Perdew, S. Burke and M. Ernserhof, Phys. Rev. Let. 77 (1996) 3865. [7]. E.L. Peltzer y Blancá, J. Desimoni, N.E. Christensen, H. Emmerich, S. Cottenier, Phys. Status Solidi B, 20 (2009)ab-initio studies of the magnetic and hyperfine properties variations with pressure of both iron sites in the structure of Fe4N, using FP-LAPW [3-5] method and the Perdew-Burke-Ernzerhof functional of the Generalized Gradient Approximation [6] was used to describe the exchange-correlation potential. The results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII presents a discontinuity when the lattice parameter is varied. This is expressed mainly in the changes of the electronic structure and specifically in the behaviour of density of states, showing a compression of electronic states in the vicinity of -3eV. Furthermore, we show a good agreement between our calculations in the equilibrium and experimental data from Mossbauer [7] of the hyperfine field, isomer shift and the electric field gradient on the two iron sites. [1]. P.H. Emmett, S.B. Hendricks, S. Brunauer, Journal of the American Chemical Society 52, (1930) 1456. [2]. K.H. Jack, Proc. R. Soc. London A 208, 216 (1951). [3]. Sinsh D., Planewaves, Pseudopotentials and the LAPW Method, Kluwer Academic Publishers 1994. [4]. R.M. Martin, Electronic Structure, Basic Theory and Practical Methods, Cambridge University Press, 2004. [5]. P. Blaha, K. Schwarz, J. Luitz, G.K.H. Madsen, D. Kvasnicka, Wien2K, Technical University of Vienna, Vienna, Austria, 2001. [6]. J.P. Perdew, S. Burke and M. Ernserhof, Phys. Rev. Let. 77 (1996) 3865. [7]. E.L. Peltzer y Blancá, J. Desimoni, N.E. Christensen, H. Emmerich, S. Cottenier, Phys. Status Solidi B, 20 (2009)4N, using FP-LAPW [3-5] method and the Perdew-Burke-Ernzerhof functional of the Generalized Gradient Approximation [6] was used to describe the exchange-correlation potential. The results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII presents a discontinuity when the lattice parameter is varied. This is expressed mainly in the changes of the electronic structure and specifically in the behaviour of density of states, showing a compression of electronic states in the vicinity of -3eV. Furthermore, we show a good agreement between our calculations in the equilibrium and experimental data from Mossbauer [7] of the hyperfine field, isomer shift and the electric field gradient on the two iron sites. [1]. P.H. Emmett, S.B. Hendricks, S. Brunauer, Journal of the American Chemical Society 52, (1930) 1456. [2]. K.H. Jack, Proc. R. Soc. London A 208, 216 (1951). [3]. Sinsh D., Planewaves, Pseudopotentials and the LAPW Method, Kluwer Academic Publishers 1994. [4]. R.M. Martin, Electronic Structure, Basic Theory and Practical Methods, Cambridge University Press, 2004. [5]. P. Blaha, K. Schwarz, J. Luitz, G.K.H. Madsen, D. Kvasnicka, Wien2K, Technical University of Vienna, Vienna, Austria, 2001. [6]. J.P. Perdew, S. Burke and M. Ernserhof, Phys. Rev. Let. 77 (1996) 3865. [7]. E.L. Peltzer y Blancá, J. Desimoni, N.E. Christensen, H. Emmerich, S. Cottenier, Phys. Status Solidi B, 20 (2009)