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NSRRC September 12 program
Part 1 CTM4XAS Atomic Multiplet, crystal fields and charge transfer Part 2 CTM4RIXS
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Charge Transfer Multiplet program
Used for the analysis of XAS, EELS, Photoemission, Auger, XES, ATOMIC PHYSICS GROUP THEORY MODEL HAMILTONIANS The TT-multiplets program can be used to explain the spectral shapes of all core level spectroscopies. XAFS, photoemission, auger, etc. The program combines three advanced computer codes, an atomic physics code to describe all atomic interactions, a group theory code to describe the local symmetry (think of crystal fields) and model Hamiltonians to describe many body effects correlated systems. AS A SIDE REMARK I WOULD LIKE TO MENTION that the active site in a catalyst is a perfect example of a correlated system. (in biocatalysis this is often realised) The integrated program gives accurate descriptions of core level spectra, from a set of uniform electronic structure parameters. The program is important for all of the new spectroscopies that I will describe. The program is distributed from my homepage and it is used at some 50 institutes worldwide.
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X-ray Absorption Spectroscopy
Excitations of core electrons to empty states The XAS spectrum is given by the Fermi Golden Rule 3
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X-ray Absorption Spectroscopy
Excitations of core electrons to empty states The XAS spectrum is given by the Fermi Golden Rule 1s 4
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X-ray Absorption Spectroscopy
Phys. Rev. B.40, 5715 (1989) 5
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X-ray Absorption Spectroscopy
oxygen 1s > p DOS Phys. Rev. B.40, 5715 (1989); 48, 2074 (1993) 6
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X-ray Absorption Spectroscopy
oxygen 1s > p DOS Phys. Rev. B.40, 5715 (1989); 48, 2074 (1993) 7
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Interpretation of XAS 1-particle: 1s edges (DFT + core hole +U)
+ all edges of closed shell systems (TDDFT, BSE) many-particle: open shell systems (CTM4XAS) 8
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XAS: multiplet effects
Fermi Golden Rule: IXAS = |<f|dipole| i>|2 [E=0] Single electron (excitation) approximation: IXAS = |< φ empty|dipole| φcore>|2 9
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XAS: multiplet effects
Overlap of core and valence wave functions Single Particle model breaks down 3d <2p3d|1/r|2p3d> 2p3/2 2p1/2 Phys. Rev. B. 42, 5459 (1990) 10
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X-ray absorption: core hole effect
XAS: recent first principles developments for L edges DFT to cluster Wannier multiplet (Haverkort) Restricted-Active-Space (Odelius, Koch, Broer, Lundberg) Extensions of TD-DFT with 2h-2e (Neese, Roemelt) ab-initio multiplets [‘RAS-DFT’] (Ikeno, Uldry) [ See 11
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CTM4XAS (semi-empirical)
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Charge Transfer Multiplet program
Used for the analysis of XAS, EELS, Photoemission, Auger, XES, ATOMIC PHYSICS GROUP THEORY MODEL HAMILTONIANS The TT-multiplets program can be used to explain the spectral shapes of all core level spectroscopies. XAFS, photoemission, auger, etc. The program combines three advanced computer codes, an atomic physics code to describe all atomic interactions, a group theory code to describe the local symmetry (think of crystal fields) and model Hamiltonians to describe many body effects correlated systems. AS A SIDE REMARK I WOULD LIKE TO MENTION that the active site in a catalyst is a perfect example of a correlated system. (in biocatalysis this is often realised) The integrated program gives accurate descriptions of core level spectra, from a set of uniform electronic structure parameters. The program is important for all of the new spectroscopies that I will describe. The program is distributed from my homepage and it is used at some 50 institutes worldwide.
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Atomic Multiplet Theory
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Atomic Multiplet Theory
Kinetic Energy Nuclear Energy Electron-electron interaction Spin-orbit coupling
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Atomic Multiplet Theory
X X Kinetic Energy Nuclear Energy Electron-electron interaction Spin-orbit coupling
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Term Symbol 2S+1L
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Term Symbols of a two-electron state
1s2s-configuration Term symbols 1s: 2S Term symbols 2s: 2S Term symbols 1s2s: multiply L and S separately L2p=0, L3p=0 >> LTOT = 0 S2p=1/2, S3p=1/2
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Term Symbols 1s2s-configuration S2p=1/2, S3p=1/2
What are the values of the total S (STOT) ? = 0 or 1 Singlet or triplet: ↑↓ or ↑↑, but the degeneracies are 1 and 3
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Term Symbols Singlet or triplet
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Spin-orbit coupling Couple L and S quantum numbers
L and S loose their exact meaning as quantum numbers Only the total moment J is a good quantum number Valence Spin-orbit coupling
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Quantum numbers Main n 1,2,3,…. Azimuthal L (orbital moment) Spin S
Magnetic mL (orbital magnetic moment) Spin magnetic mS (spin magnetic moment) Total moment J Total magnetic mJ
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Term Symbols Term symbols of a 2p13d1 configuration
2p1 2P1/2, 2P3/2 (S=1/2, L=1) 3d1 2D3/2, 2D5/2 (S=1/2, L=2) 2p13d STOT = 0 or 1 LTOT = 1 or 2 or 3 1P1 + 3P0, 3P1, 3P2 1D2 + 3D1, 3D2, 3D3 1F3 + 3F2, 3F3, 3F4 [(2J+1)= =60]
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Term Symbols Term symbols of a 2p2 configuration
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Configurations of 2p2 1 0 -1 1 0 -1 1 0 -1 1 0
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1S0 1D2 3P0 3P1 3P2 Term Symbols of 2p2 MS=1 MS=0 MS=-1 ML= 2 1 ML= 1
1 ML= 1 2 ML= 0 3 ML=-1 ML=-2 LS term symbols: 1S, 1D, 3P LSJ term symbols: 1S0 1D2 3P0 3P1 3P2
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The electron-electron interaction
Electron-electron interaction acts on 2 electrons It can couple 4 different wave function a, b, c and d
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The electron-electron interaction
Split wave functions into radial and angular part Split operator into radial and angular part Use series expansion of 1/r12
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Coulomb integral Special case: a=c and b=d
>> the two electron are in the same shell Fk is called a Slater integral It is a number that is calculated from first principles
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Atomic Multiplet Theory
Electron-electron interactions of Valence States Valence Spin-orbit coupling
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CTM4XAS version 5.2
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CTM4XAS version 5.2
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Atomic Multiplet Theory
Core Valence Overlap Core Spin-orbit coupling
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Multiplet Effects (Ni2+)
0.07 5 8 17 13 2 Core Valence Overlap Core Spin-orbit coupling
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2p XAS of TiO2 Ground state is 3d0 Dipole transition 3d02p53d1
Ground state symmetry: 1S0 Final state symmetry: 2P2D gives 1P, 1D, 1F, and 3P, 3D, 3F
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2p XAS of TiO2 Final state symmetries: 1P, 1D, 1F, and 3P, 3D, 3F
Transition <1S0|J=+1| 1P1, 3P1 , 3D1> 3 peaks in the spectrum
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Exercise: Calculate the 2p XAS spectrum of a Ti atom
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Hunds rules Give the Hund’s rule ground states for 3d1 to 3d9
Term symbols with maximum spin S are lowest in energy, Among these terms: Term symbols with maximum L are lowest in energy In the presence of spin-orbit coupling, the lowest term has J = |L-S| if the shell is less than half full J = L+S if the shell is more than half full 3d1 has 2D3/2 ground state d2 has 3F2 ground state 3d9 has 2D5/2 ground state d8 has 3F4 ground state Give the Hund’s rule ground states for 3d1 to 3d9
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Exercise: Calculate the 2p XAS spectrum of Fe
Fe atom: Ground state: 3d6 (4s2) 5D j=4
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Term Symbols and XAS Fe atom: Ground state: 3d6 (4s2)
Final state: 2p53d7 Dipole transition: p-symmetry 3d6-configuration: 5D, etc. j=4 2p53d7-configuration: 110 states j’= 3,4, 5 p-transition: 1P j=+1,0,-1 ground state symmetry: 5D D4 transition: 5D 1P = 5PDF possible final states: states
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Term Symbols and XAS Fe atom: Ground state: 3d6 (4s2) 5D j=4 5D0 5D
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Term Symbols and XAS NiII ion in NiO: Ground state: 3d8
Final state: 2p53d9 Dipole transition: p-symmetry 3d8-configuration: 1S, 1D, 3P,1G, 3F j=4 2p53d9-configuration: 2P2D = 1,3PDF j’=0,1,2,3,4 p-transition: 1P j=+1,0,-1 ground state symmetry: 3F 3F4 transition: 3F 1P = 3DFG two possible final states: 3D, 3F 3D3,3F3,3F4, 1F3
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3d8 XAS calculation +LS3d : > 3F4 +LS2p +FK, GK: > 3F
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Atomic multiplets
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Charge Transfer Multiplet program
ATOMIC PHYSICS GROUP THEORY MODEL HAMILTONIANS The TT-multiplets program can be used to explain the spectral shapes of all core level spectroscopies. XAFS, photoemission, auger, etc. The program combines three advanced computer codes, an atomic physics code to describe all atomic interactions, a group theory code to describe the local symmetry (think of crystal fields) and model Hamiltonians to describe many body effects correlated systems. AS A SIDE REMARK I WOULD LIKE TO MENTION that the active site in a catalyst is a perfect example of a correlated system. (in biocatalysis this is often realised) The integrated program gives accurate descriptions of core level spectra, from a set of uniform electronic structure parameters. The program is important for all of the new spectroscopies that I will describe. The program is distributed from my homepage and it is used at some 50 institutes worldwide.
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Crystal Field Effects eg states t2g states
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Octahedral crystal field splitting
metal ion in free space in symmetrical field t2g yz xz xy eg in octahedral ligand field x2-y2 z2 x2-y2 yz z2 xz xy
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Crystal Field Effects in CTM
7 = 2.13 eV
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Crystal Field Effects SO3 Oh (Mulliken) S A1 P 1 T1 D 2 E+T2 F 3
A1 P 1 T1 D 2 E+T2 F 3 A2+T1+T2 G 4 A1+E+T1+T2
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2p XAS of TiO2 (atomic multiplets)
TiIV ion in TiO2: 3d0-configuration: 1S, j=0 2p13d9-configuration: 2P2D = 1,3PDF j’=0,1,2,3,4 p-transition: 1P j=+1,0,-1 Write out all term symbols: 1P1 1D2 1F3 3P0 3P1 3P2 3D1 3D2 3D3 3F2 3F3 3F4
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Crystal Field Effect on XAS
J in SO3 Deg. 1 3 2 4 12 <1S0|dipole|1P1> goes to <A1|T1|T1>
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Crystal Field Effect on XAS
J in SO3 Deg. Branchings 1 A1 3 3T1 2 4 4E, 4T2 3A2, 3T1,3T2 A1, E, T1, T2 12 <1S0|dipole|1P1> goes to <A1|T1|T1>
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Crystal Field Effect on XAS
J in SO3 Deg. Branchings in Oh 1 A1 2 3 3T1 A2 4 4E, 4T2 T1 7 3A2, 3T1,3T2 T2 8 A1, E, T1, T2 E 5 12 25 <1S0|dipole|1P1> goes to <A1|T1|T1>
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Effect of 10Dq on XAS:3d0
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Comparison with Experiment
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Comparison with Experiment
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CTM4XAS version 5.2
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CTM4XAS version 5.2
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Turning multiplet effects off
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Hunds rules Term symbols with maximum spin S are lowest in energy,
Among these terms: Term symbols with maximum L are lowest in energy In the presence of spin-orbit coupling, the lowest term has J = |L-S| if the shell is less than half full J = L+S if the shell is more than half full 3d1 has 2D3/2 ground state d2 has 3F2 ground state 3d9 has 2D5/2 ground state d8 has 3F4 ground state
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Crystal Field Effects on 3d8 states
Energy Symmetries Oh Total symmetry 1S 4.6 eV 1A1 3P 0.2 eV 3T1 1D -0.1 eV 1E + 1T2 3F -1.8 eV 3A2 + 3T1 + 3T2 1G 0.8 eV 1A1+1T1+1T2+1E
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Crystal Field Effects SO3 Oh (Butler) Oh (Mulliken) S A1 P 1 T1 D 2
A1 P 1 T1 D 2 2 + ^1 E+T2 F 3 ^0+ 1 +^1 A2+T1+T2 G 4 ^1 A1+E+T1+T2
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Double group symmetry A1A1=A1 T1T2= T1+ T2+ E+ A2 Symmetries Oh
Energy Symmetries Oh Total symmetry 1S 4.6 eV 1A1 3P 0.2 eV 3T1 1D -0.1 eV 1E + 1T2 3F -1.8 eV 3A2 + 3T1 + 3T2 1G 0.8 eV 1A1+1T1+1T2+1E A1A1=A1 T1T2= T1+ T2+ E+ A2
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Crystal Field Effects: Tanabe-Sugano
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Effect of 10Dq on XAS:3dN
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High-spin or Low-spin 10Dq > 3J (d4 and d5) 10Dq > 2J
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2p XAS of Mn2+
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3d spin-orbit coupling Exercise: Calculate the 2p XAS spectrum of CoO
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3d spin-orbit coupling
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Charge Transfer Effects
Ground state of a transition metal system 3dN at every site Charge fluctations
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Charge Transfer Effects
Hubbard U for a 3d8 ground state: U= E(3d7) + E(3d9) – E(3d8) – E(3d8) Ligand-to-Metal Charge Transfer (LMCT): = E(3d9L) – E(3d8)
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Charge Transfer Effects
= E(3d9L) – E(3d8) E(3d10LL‘) – E(3d8) Two times charge transfer: 2 Extra 3d3d interaction: U 2 +U
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Charge Transfer Effects
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Charge Transfer Effects in XAS
E(3d9L) – E(3d8) = E(3d10LL‘) – E(3d8) = 2 +U 2p XAS: 3d8 2p5 3d9 E (2p53d9) = E2p+ 2p XAS: 3d9L 2p5 3d10L E (2p53d10L) = E2p- Q +2+U Energy difference: E2p- Q +2+U- E2p - = +U-Q Q U+2 eV
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Charge Transfer Effects in XAS
+U-Q
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Charge Transfer Effects
MnO: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d5 2p53d6
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Charge Transfer Effects
MnO: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d6L 3d5 2p53d7L 2p53d6 +U-Q
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Charge Transfer Effects in XPS
-Q
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Charge transfer effects in XAS and XPS
Transition metal oxide: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d6L XPS 2p53d5 XAS 2p53d7L 3d5 -Q Ground State +U-Q 2p53d6L 2p53d6
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Charge Transfer Effects
NiO: Ground state: 3d8 (3d8 ) + 3d9L Charge transfer energy + 3d93d7 Hubbard U + 3d10L2 2+U + 3d7L Metal-ligand CT MLCT
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Charge Transfer Multiplets of Ni2+
=3 =9 =0 =6
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Exercise: perform a series of charge transfer calculations changing from +10 to -10.
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X-ray Absorption Spectroscopy
Spectral shape: (1) Multiplet effects (2) Charge Transfer J. Elec. Spec. 67, 529 (1994)
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Charge transfer
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Charge transfer
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Charge transfer
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Charge Transfer effects
3d8 + 3d9L =10 30% 3d8 1A1 =5 NiO =0 30% 3d8 3A2 La2Li½Cu½O4 =-5 =-10 Chem. Phys. Lett. 297, 321 (1998)
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Charge Transfer effects
3d8 + 3d9L =10 30% 3d8 1A1 =5 NiO =0 30% 3d8 3A2 La2Li½Cu½O4 =-5 =-10 Calculate the 2p XAS spectrum of Cs2KCuF6
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LMCT and MLCT: - bonding
FeIII: Ground state: 3d5 + 3d6L 3d6L 3d5 2p53d7L 2p53d6 +U-Q with Ed Solomon (Stanford) JACS 125, (2003), JACS 128, (2006), JACS 129, 113 (2007)
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LMCT and MLCT: - bonding
FeIII: Ground state: 3d5 + 3d6L + 3d4L 2p53d5L 2p53d7L 2p53d6 3d4L 3d6L 3d5 -U+Q + 2 +U-Q - 2 with Ed Solomon (Stanford) JACS 125, (2003), JACS 128, (2006), JACS 129, 113 (2007)
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LMCT and MLCT: - bonding
FeIII(tacn)2 FeIII(CN)6 with Ed Solomon (Stanford) JACS 125, (2003), JACS 128, (2006), JACS 129, 113 (2007)
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RIXS
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RIXS Butorin, J. Elec. Spec. 110, 213 (2000)
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Resonant Inelastic X-ray Spectroscopy
dd excitation
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Resonant Inelastic X-ray Spectroscopy
2p XAS of CaF2 3d0 ’ 3s13d1 2p53d1
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Resonant Inelastic X-ray Scattering
2p3s RIXS of CaF2 3d0 ’ 3s13d1 2p53d1 Phys. Rev. B. 53, 7099 (1996)
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Resonant Inelastic X-ray Spectroscopy
Butorin J. Elec. Spec 110, 213 (2000) Exercise: Repeat these calculations
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Soft x-ray RIXS and magnetism
NiII 3d8 [] 2p53d9[jj] 3d8[]
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Soft x-ray RIXS and magnetism
MS dd ‘spin-flip’ spin-flip Phys. Rev. B. 57, (1998) 2p3d RIXS of NiO
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CTM4RIXS
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CTM4RIXS What does the progam do? What does the program do?
Nothing, really… no multiplets, no group theory, no angular dependence, …) Takes output of two separate ctm4xas calculations and combines them in Kramers-Heisenberg Formula
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CTM4RIXS
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CTM4RIXS Load in absorption and emission files → Extract information and save energies, symmetries and transition matrix elements (saved as .sm file). >> These matrices are calculated with CTM4XAS if the RIXS option is chosen Emission Triad IS → T2 → FS Absorption Triad GS → T1 → IS |g>, Eg |n>, En |f>, Ef W w W - w
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A first CTM4RIXS calculation
Choose the name_abs that has been calculated with CTM4XAS
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A first CTM4RIXS calculation
Choose ‘1’ in the pop-up menu
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A first CTM4RIXS calculation
Choose ‘1’ in the pop-up menu
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A first CTM4RIXS calculation
Click button at bottom
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A first CTM4RIXS calculation
Set L intermediate to 0.4 and click button at bottom
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A first CTM4RIXS calculation
Set Delta to 0.1 (two times) and click button at bottom Choose a name in the pop-up window.
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A first CTM4RIXS calculation
Set Delta NOT to a small number >> CTM4RIXS crashes
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A first CTM4RIXS calculation
Start the calculation with the RIXS button A pop-up window tracks the progress.
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CTM4RIXS The RIXS calculation is finished.
Next the RIXS plane can be plotted with the screen on the right.
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Plotting a CTM4RIXS calculation
Select the file button and next the select the file you calculated; GOTO the name_RIXS directory GOTO the name_matrices directory SELECT name_Ms
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Plotting a CTM4RIXS calculation
This is the 2p3d RIXS plane of Ni2+ with 10Dq=1.0 eV.
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Plotting a CTM4RIXS calculation
Enlarge a region of the 2D map with this button & select the region.
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Plotting a CTM4RIXS calculation
Final state energy to set the vertical axis to energy loss. (& enlarge/select the region).
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Selecting a cross-section
Choose a vertical cross section & select energy. The screen on the right shows the cross section (= RXES)
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What is calculated with CTM4RIXS
2D RIXS plane Cross sections, including resonant XES selective XAS HERFD partial FY
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What is NOT calculated with CTM4RIXS
No interatomic exchange (can be included) Only 3dN > 2p5 3dN+1 > 3dN channel (as yet) no charge transfer Fluorescence is not included
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A first CTM4RIXS calculation
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Calculations without the CTM4XAS interface
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS without charge transfer (note: this is a repetition of CTM4XAS, now with the original DOS commands) Do a CTM4XAS calculation for 2p3d RIXS, for example for Co2+, 10dq=1 eV, using co2 as filename. Copy the files co2_ems.rcg, co2_abs.rcg, co2_ems.rac and co2_abs.rac to the directory c:cowan/batch Open the DOS prompt command window, for type cmd in “search programs” Goto the directory c:/cowan/batch by typing ‘cd ..’, ‘cd ..’, ‘cd cowan’, ‘cd batch’ type ‘rcg2 co2_ems’ and ‘rac2 co2_ems’. Same for the _abs files. Open the ora-files with CTM4RIXS and make a plot (same as with CTM4XAS files) (shift the excitation energy and the emission energy to the correct values)
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Calculations without the CTM4XAS interface
Calculation of 2p3s RIXS (without charge transfer) Do a CTM4XAS calculation for 2p3d RIXS, for example for Co2+, 10dq=1 eV. Do a RCN calculation using hco23s.rcn within c/cowan/batch; The output is written in the file hco23s.rcf Open the file co2p3s_ems.rcg and change the line P_5__D_8 to P_5__D_8__S_2 (keep the same number of spaces indicated by _). Change the line P_6__D_7 to P_6__D_8__S_1. Open the file hco23s.rcf and copy the line starting with “Co2+ 3s01 3d08” and replace in co2p3s_ems the line starting with “Co2+ 2P06 3D07”. Change the energy to (from a value around -600). Re-run the rcg and rac files for 2p3s RIXS. Open the ora-files with CTM4RIXS and make a plot. (shift the excitation energy and the emission energy to the correct values) (Note that the integrated XES spectrum now gives exactly the XAS spectral shape because it is a core-core channel)
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS with charge transfer (MATLAB is needed) Step 1: run CTM4XAS RUN an XAS calculation with CTM4XAS, including charge transfer. Use any name. I use nitest1, with 10Dq=1, DELTA=3, Udd=6, Upd=7, rest=default. Copy the files nitest1.rcg and nitest1.ban to cowan/batch Copy in cowan/batch rni2.rac to nitest1.rac
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS with charge transfer (MATLAB is needed) Step 2: Run the calculations for absorption Copy BANEX2.BAT to cowan/batch #see below# Copy banderex.exe to cowan/bin ## Open the DOS prompt Change the directory to c:cowan/batch Type Rcg2 nitest1 Type Rac2 nitest1 Type Banex2 nitest1 The result is in the file nitest1.oba (## this is a modified executable file using exact diagonalization as created by Robert Green; ask me to send it to you)
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS with charge transfer (MATLAB is needed) Step 3a: Create the inputfiles for the x-ray emission step and run the calculations Copy nitest1.rcg to nitest1x.rcg Edit the file nitest1x.rcg Invert lines 4 and 5 (line 4 is D08 P06) Invert lines 12 and 13 Invert block 4 with block 3. [Each block starts with …. and ends with ] Save the file nitest1x.rcg Copy nitest1.rac to nitest1x.rac Copy nitest1.ban to nitest1x.ban
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS with charge transfer (MATLAB is needed) Step 3b: Edit the file nitest1x.ban Change the lines def EG2 = unity def EF2 = unity to def EG2 = unity def EF2 = unity Change for the triads the first sign from + to – and the last sign from – to + Change erange 0.3 to erange 999 Type Rcg2 nitest1x Type Rac2 nitest1x Type Banex2 nitest1x The result is in the file nitest1x.oba
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Calculations without the CTM4XAS interface
Calculation of 2p3d RIXS with charge transfer (MATLAB is needed) Step 4: Run the Kramers-Heisenberg calculation (for the moment use this procedure; all parameters are set in racin.m) Copy nitest1.oba to rni2.oba Copy nitest1x.oba to rni2x.oba Start MATLAB Type dorixs The RIXS matrix is saved in rni2_MS Change the name rni2_MS to rni2_MS.mat Step 5: Plot with CTM4RIXS Load the file rni2_Ms.mat
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XES calculations
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X-ray absorption and X-ray photoemission
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Core Hole Decay Fluorescence Auger
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X-ray emission
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Resonant X-ray emission spectroscopy
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1s X-ray emission MnO explain axes Start with K alpha
address resolution -> no solid state detector Nomenclature from early days of x-ray spectroscopy of high Z materials (Kb3 3p1/2, Kb2 4p, Kb5 3d)
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1s X-ray emission 1s13dn Total Energy 2p53dn 3p53dn Core Hole
Ka K Main Lines K Satellites Total Energy 2p53dn Photoionization or K capture Transitions that give rise to the fluorescence lines Spectra repeated for orientation total energy of the atom on y-axis Dipole selection rules Kb satellites Core hole final states In this talk I will focus on Kbeta emission 3p53dn Core Hole Ground State Valence hole 3dn
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Multiplet effects in 1s3p XES (Kβ)
Etotal 3d 1s Kb Fluorescence Photoionization 3d 3p Strong interaction between unfilled 3p and 3d shells!
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Spin-selectivity in the Kb line
Multiplet effects in 1s3p XES (Kβ) Spin-selectivity in the Kb line 3d 7P 3p 5P ? 3d 3p Kb1,3 Kb’
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Multiplet effects in 1s3p XES (Kβ)
3p XPS and Kb XES Multiplet effects in 1s3p XES (Kβ) Identical final state configuration: 3p53d5 A Free Mn atom 3p XPS B MnF2 Kb F
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1s2p and 1s3p XES spectra
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1s2p and 1s3p XES spectra Approximations: 3dN ground state (+ CT)
XES only from lowest energy 1s13dN state (+CT) Charge transfer energy is -Q
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Charge transfer in 1s pre-edge and edge
Transition metal oxide: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d6L edge 1s13d5 Pre-edge 1s13d7L 3d5 -Q Ground State +U-Q 1s13d6L 1s13d6
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1s2p and 1s3p XES spectra Approximations: 3dN ground state (+ CT)
XES only from lowest energy 1s13dN state (+CT) Charge transfer energy is -Q Neglect 1s3d exchange interaction (needed for spin-pol.) Neglect of excitation process (a better approximation is to describe the excitation process with XPS)
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Charge transfer in XES spectra
Pieter Glatzel et al. Phys. Rev. B. 64, (2001)
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Charge transfer in XES spectra
Pieter Glatzel et al. Phys. Rev. B. 64, (2001)
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RIXS at metal K edges
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Fe K pre-edges Exercise: Repeat these calculations
Westre et al. JACS 119, 6297 (1997); Heyboer et al. J.Phys.Chem.B. 108, (2004)
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Pre-edge and edge Exercise: Repeat these calculations CoO
high-spin CoII 3d7 [4T2] Only quadrupole peaks visible 3d7 1s13d8 2p53d8 Only correct with interference effects ON
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Non-local screening peaks RIXS-MCD at the K pre-edge
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Non-local screening peaks RIXS-MCD at the K pre-edge
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Non-local screening peaks RIXS-MCD at the K pre-edge
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Non-local screening peaks RIXS-MCD at the K pre-edge of Fe3O4
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RIXS-MCD at the K pre-edge Non-local screening peaks
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Non-local screening peaks RIXS-MCD at the K pre-edge
XMCD at high-pressure Sikora, PRL 105, (2010)
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MCD
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X-MCD
156
light polarization q = mJ
X-MCD Cu2+: 3d p53d10 L=2, S=1/2 2D J=5/2 or 3/2 More than half-full 2D5/2 L=1, S=1/2 2P J=3/2 or 1/2 2P3/2 or 2P1/2 J= +1 or 0 or -1 light polarization q = mJ
157
X-MCD Cu2+: 3d9
158
X-MCD Exercise: Repeat these calculations mJ=-5/2 MCD to mJ’=-3/2
no LS MCD Exercise: Repeat these calculations
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X-MCD MCD no LS MCD + crystal field
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X-MCD MCD 3F LS 3F no LS
161
XPS
162
X-ray photoemission
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Charge transfer effects in XPS
164
Charge Transfer Effects in XAS
+U-Q
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Charge Transfer Effects
MnO: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d5 2p53d6
166
Charge Transfer Effects
MnO: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d6L 3d5 2p53d7L 2p53d6 +U-Q
167
Charge Transfer Effects in XPS
-Q
168
Charge transfer effects in XAS and XPS
Transition metal oxide: Ground state: 3d5 + 3d6L Energy of 3d6L: Charge transfer energy 3d6L XPS 2p53d5 XAS 2p53d7L 3d5 -Q Ground State +U-Q 2p53d6L 2p53d6
169
Charge transfer effects in XPS
Exercise: Calculate the 2p XPS spectrum of NiCl2
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