Lecture given at the conference: Simulations and Dynamics for Nanoscale and Byological Systems, held in Tokyo 2009, in honor of Professor Kimihiko Hirao

1. Ab initio studies on the luminescence of f-elements in solids Luis Seijo Departamento de Química Universidad Autónoma de Madrid http://www.uam.es/quimica/aimp

3. Context and motivation

4. Excited states of f-elements in solids Lanthanides: SSL (Solid-State Lighting) Actinides: ANES (Advanced Nuclear Energy Systems) Design of phosphors Fundamental studies Fundamental studies Ce 3+ :Y 3 Al 5 O 12 U 4+ ,Pu 4+ :UO 2 ,PuO 2 Divalent lanthanides e.g. e.g. e.g.

10. Methodological details Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

12. An embedded-cluster model of Yb 2+ :CsCaBr 3 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

13. Embedding AIMP’s point-charge Coulomb (Madelung) finite-size Coulomb exchange linear-independence (Pauli) Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Out of self- c onsistent HF embedded-ions calculations on the undoped solid MOLCAS MakeAIMP SCEI

18. Results Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

19. Dynamic correlation effects SA-CASSCF MS-CASPT2 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

20. Nature of the lowest 4f 13 5d 1 states Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

21. Spin-orbit coupling effects Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu MS-CASPT2 sfss-SOCI 1 T 1u ED allowed T 1u ED forbidden Low-spin? High-spin?

22. States’ character. 4 f 13 [7/2]  5d(t 2g ) 1 manifold Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu State 1A 1g  f  10 2 Term analysis (%) 3 T 1u 3 T 2u 3 E u 3 A 1u 1 T 1u 1 T 2u 1 E u 1 2 3 1 2 1 2 1 1 2 3 1 1 1T 2u 23890 90 1E u 23900 90 6 1T 1u 26560 0.273 9 38 12 34 2T 1u 26600 1.260 32 12 6 14 7 15 10 2T 2u 26720 22 10 32 34 ... 3T 1u 27200 0.030 24 12 9 4 1 45 ... 4T 1u 28360 0.000 32 47 9 ... 5T 1u 29070 0.084 6 16 12 21 8 28 ... 6T 1u 29880 0.489 5 43 5 39 4 2

24. 4f N-1 5d 1 HS and LS of heavy Ln 2+ in solids 4f N-1 5d 1 4f N Low-spin states Low-spin ground state gap spin-forbidden spin-allowed High-spin states Bunch of mixed-spin states Low-spin ground state gap spin-forbidden spin-enabled Isolated  pure high-spin states Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

25. 4f N-1 5d 1 HS and LS of heavy Ln 2+ in solids 4f N-1 5d 1 4f N Low-spin states Low-spin ground state gap spin-forbidden spin-allowed High-spin states Bunch of mixed-spin states Low-spin ground state gap spin-forbidden spin-enabled Isolated  pure high-spin states Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

26. 4f 13 5d(t 2g ) 1 manifold of Yb 2+ :CsCaBr 3 LS HS MS

27. 4f  5d(t 2g ) ED-allowed absorption spectrum Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu spin-forbidden transitions to high-spin states Intensity (arbitrary units) spin-enabled transitions to mixed-spin states

29. Details of the whole 4f 13 5d 1 manifold. Several emissions? Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

30. 4f 13 5d 1 and 4f 13 6s 1 manifolds of Yb 2+ :CsCaBr 3 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu MS-CASPT2 sfss-SOCI without spin-orbit with spin-orbit

31. Full 4f  5d ED-allowed absorption spectrum Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

32. Potentially emitting levels Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

33. Potentially emitting levels configuration level spin character gap calculation experiment transition HS 23900 128 spin-forbidden 23900 23000 MS 2600 13 spin-enabled 26500 24500 HS 4600 24 spin-forbidden 34600 HS 4000 22 spin-forbidden 43900 HS 5200 30 spin-forbidden 53900 in CB

34. Conclusions Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu