raimund feifel uppsala university/stockholm university ([email protected]) a double
TRANSCRIPT
![Page 1: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/1.jpg)
Raimund FeifelUppsala University/Stockholm University
http://usxs.fysik.uu.se/projectweb/portalproject/MEICSAM.html
A double time-of-flight multi-electron-ion coincidence spectroscopy technique
![Page 2: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/2.jpg)
In memory of Fabian Österdahl
![Page 3: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/3.jpg)
Historical overview
![Page 4: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/4.jpg)
Historical overview
![Page 5: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/5.jpg)
Photoionisation
Photoelectric law, A. Einstein 1905: h = Ekin+ EB
IP
=
![Page 6: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/6.jpg)
Photoelectron spectroscopy
+
-
h
A
e - (E kin )
FÖRE EFTER
A+
h + EA → EA+ + EkinEkin = h - EB
Before
After
Kai Siegbahn et al., Uppsala University
![Page 7: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/7.jpg)
Photoelectron spectroscopy today
Bl I411 @ MAX-lab, Lund, Sweden
![Page 8: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/8.jpg)
Photoelectron spectrum of Argon
Electron binding energy (eV)18 17 16 15 14 13
Inte
nsity
Ar
3p
2P3/22P1/2 Spin-orbit
components
Dept. of Physics, course laboratory spectrometer
Intensity ratio 2 : 4
![Page 9: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/9.jpg)
Ar+ - one electron lessElectron configuration
1s2 2s2 2p6 3s2 3p5 (2P3/2, 2P1/2) Ar+
MJ = - J, -J+1, …, J-1, J
![Page 10: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/10.jpg)
Photoexcitation and ionisation processes
![Page 11: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/11.jpg)
Deexcitation processes
![Page 12: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/12.jpg)
Single photon - multiple ionisation
Double (multiple) ionisation energy (DIP, …)
EB1 + EB2 (+ …) = h - Ekin1 - Ekin2 (- …)
![Page 13: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/13.jpg)
TOF-PEPECO spectroscopy
J.H.D. Eland et al., Phys. Rev. Lett. 90, 053003, 2003
e-
e-
e-
e-
several m
€
t =D
EKin
![Page 14: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/14.jpg)
TOF-PEPECO instrument…
World’s longest electron time-of-flight spectrometer
![Page 15: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/15.jpg)
… now operational at AlbaNova…
![Page 16: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/16.jpg)
… and it’s ‘little brother’
![Page 17: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/17.jpg)
Timing principle
![Page 18: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/18.jpg)
Single photon - double ionisation of Argon (h
= 48.372 eV)
deadtime ~ 50 ns
![Page 19: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/19.jpg)
Double ionisation spectrum of Ar
Electron configuration:1s2 2s2 2p6 3s2 3p4 (3P2,1,0, 1D2, 1S0) Ar2+
![Page 20: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/20.jpg)
Ar2+, Kr2+ and Xe2+
![Page 21: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/21.jpg)
Rule-of-thumbLowest
DIP (eV)
Lowest
IP (eV)*
Ratio
DIP/IP
Ar 43.39 15.76 2.75
Kr 38.36 14.00 2.74
Xe 33.11 12.13 2.73
€
DIPlow ≈ 2.7 ⋅ IPlow
*PhysicsHandbook
empirically To appear in Kosmos 2007
![Page 22: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/22.jpg)
Rule-of-thumb for molecules
€
DIPlow ≈ 2.0 ⋅ IPlow +11.5 ⋅1
r12empirically R.D. Molloy et al., Chem. Phys.
335, 49 (2007)P. Linusson et al., in manuscript 2008
![Page 23: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/23.jpg)
Possible double ionisation processes
•A + h A2+ + 2e- (direct double ionisation; continuous energy sharing)
•A + h A+* + 1e- A2+ + 1e- (indirect double ionisation involving discrete intermediate states)
![Page 24: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/24.jpg)
Formation of Xe2+ states
![Page 25: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/25.jpg)
Xe+ intermediate states
![Page 26: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/26.jpg)
A polyatomic example: SF6
![Page 27: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/27.jpg)
Electron distribution of SF6
2+
![Page 28: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/28.jpg)
Differently selected SF62+
spectra
‘complete’ e- e- spectrum
E1: 0 - 1 eV @ 38 eV
E1: 0 - 0.1 eV @ 38 eV; akin “TPEsCO”
Slice of 2 eV @ 38 eV; “direct” SF62+
R. Feifel, J.H.D. Eland, L. Storchi and F. Tarantelli, J. Chem. Phys. 122, 144309, 2005
![Page 29: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/29.jpg)
![Page 30: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/30.jpg)
Double ionisation energy (eV)
560 570 580 590 600
Core valence double ionisation of O2
E. Andersson, M. Stenrup et al. , in preparation
![Page 31: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/31.jpg)
TOF-PEPEPIPICO spectroscopy
e-
e-
e-
e-
i++
i++
i+
i+
Simultaneously possible to conduct:
1) Electron-ion coincidence (PEPICO)
2) Electron-ion-ion coincidence (PEPIPICO)
3) Electron-electron coincidence (PEPECO)
4) Electron-electron-ion coincidence (PEPEPICO)
5) Electron-electron-ion-ion coincidence (PEPEPIPICO)
… “PE(n)PI(m)CO experiment”; n, m = 0, 1, 2…
fe ~ 40%
fi ~ 10%
2 m
J.H.D Eland and R. Feifel Chem. Phys. 327 85 (2006)R. Feifel et al., J. Chem. Phys. 125, 194318 (2006)
![Page 32: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/32.jpg)
Mass selected TOF-PEPECO spectra of CS2
Collection efficiencies for ions
taken into account
Threshold for CS+ + S+ formation ~ 29.3 eV
![Page 33: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/33.jpg)
Breakdown diagrams
![Page 34: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/34.jpg)
Two-dimensional mass spectra, e.g. CS+ + S+
KER as function of dication internal energy
![Page 35: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/35.jpg)
Summary:•Time-Of-Flight PhotoElectron-PhotoElectron COincidence spectroscopy reveals electronic states of doubly-ionised systems in direct analogy to PES
•Rules-of-thumb for double ionisation
•Direct vs. indirect double ionisation mechanisms
•TOF-PEnPImCO spectroscopy
![Page 36: Raimund Feifel Uppsala University/Stockholm University (raimund.feifel@fysik.uu.se) A double](https://reader034.vdocuments.net/reader034/viewer/2022051417/56649f3a5503460f94c571a9/html5/thumbnails/36.jpg)
AcknowledgmentsStockholm:•Mats Larsson•Tony Hansson•Fabian Österdahl•Tomasz Kloda•Isak Bakken•Mohamed Elsakre•Kjell Schmidt & workshops•Meryll Colombet
Uppsala:•Leif Karlsson•Jan-Erik Rubensson•Egil Andersson•Lage Hedin•Martin Berglund•Pelle Linusson•Aila Gengelbach•Pernilla Andersson•Tommy Karlsson•Benedikt PfeifferOxford:
•John H.D. Eland
Swedish Research Council (VR), Göran Gustafsson (UU/KTH),
Knut & Alice Wallenberg and Wenner Gren Foundations