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A Born-Oppenheimer Expansion in a Neighborhood of a Renner ...

We recognize that the component equations are **of** the same form as the radial equation for angular momentum 1 states **of** the two dimensional Isotropic Harmonic Oscillator. From the first component equation, the eigenvalues and eigenfunctions (non-normalized) are EN+ = (2N+ � + 2) 1 + ˜b , ⎛ ⎝ ˜ r+ L1 ( ˜ N+ r+ 2 )e− ˜ r+ 2 ⎞ /2 ⎠ , 0 N+ = 0,1,2, · · · where r+ ˜ = (1+ ˜b) 1/4 r. From the second component equation, the eigenvalues and eigenfunctions (non-normalized) are EN− = (2N− � + 2) 1 − ˜b , where r− ˜ = (1 − ˜b) 1/4 r. ⎛ ⎝ 0 r− ˜ L1 ( ˜ N− r− 2 )e− ˜ r− 2 /2 ⎞ ⎠ , N− = 0,1,2, · · · S**in**ce H2 is unitarily equivalent to √ a HU, we see these states give rise to eigenvalues and eigenfunctions **of** H2 given by EN− = (2N− + 2) √ a − b Ψ [l=0] (ρ,φ) = N− where r− ˜ = (a − b) 1/4 ρ, and ⎛ ⎝ − ˜ r− s**in**(φ)L1 ( ˜ N− r− 2 )e− ˜ r− 2 /2 r− ˜ cos(φ)L1 ( ˜ N− r− 2 )e− ˜ r− 2 /2 EN+ = (2N+ + 2) √ a + b Ψ [l=0] (ρ,φ) = N+ where r+ ˜ = (a + b) 1/4 ρ. ⎛ ⎝ ˜ r+ cos(φ)L1 ( ˜ N+ r+ 2 )e− ˜ r+ 2 /2 r+ ˜ s**in**(φ)L1 ( ˜ N+ r+ 2 )e− ˜ r+ 2 /2 ⎞ ⎠ , N− = 0,1,2, · · · (5.1) ⎞ ⎠ , N+ = 0,1,2, · · · (5.2) 5.2 The Perturbation Calculation For the l �= 0 States In this case, HUZ reduces to H [±|l|] UZ = ⎛ ⎜ − ⎜ ⎝ 1 2 ∂2 1 − ∂r2 2r + ˜b 2 r2 � 0 1 1 0 ∂ ∂r � + 1 2 r2 + (|l| ∓ 1)2 2r 2 0 − 1 2 . 34 ∂2 1 − ∂r2 2r ∂ ∂r 0 + 1 2 r2 + (|l| ± 1)2 2r 2 ⎞ ⎟ ⎠

Denote the eigenfunctions **of** H [±|l|] UZ by eigenfunction **of** H [|l|] UZ with eigenvalue E, then ⎛ ⎝ f[±|l|] (r) g [±|l|] ⎞ ⎛ ⎠. It is clear that if ⎝ (r) f[|l|] (r) g [|l|] ⎞ ⎠ is an (r) ⎛ ⎝ f[−|l|] (r) g [−|l|] (r) ⎞ ⎠ = ⎛ ⎝ g[|l|] (r) f [|l|] (r) ⎞ ⎠ is an eigenfunction **of** H [−|l|] UZ with eigenvalue E. So we only need to f**in**d the eigenfunctions and eigenvalues **of** the H [|l|] UZ . We have not been able to solve for the eigenvalues and eigenfunctions **in** this case exactly. We use regular perturbation theory with perturbation parameter ˜b, lett**in**g H [|l|] UZ = H[|l|] 0 +˜b ˜ V , where H [|l|] ⎛ ⎜ − ⎜ 0 = ⎜ ⎝ 1 ∂ 2 2 1 ∂ 1 − + ∂r2 2r ∂r 2 r2 (|l| − 1)2 + 2r2 0 0 − 1 ∂ 2 2 1 ∂ 1 − + ∂r2 2r ∂r 2 r2 (|l| + 1)2 + 2r2 ⎞ ⎟ ⎠ ˜V = 1 2 r2 � 0 1 1 0 � . One can show us**in**g the relative bound found **in** equation (4.2), that ˜ V is relatively bounded with respect to H [|l|] 0 on H. So, we know that **in** terms **of** ˜b, H [|l|] UZ is an analytic family **of** type A for small ˜b [19]. Therefore, the eigenvalues and eigenfunctions will be analytic functions **of** ˜b **in** a neighborhood **of** ˜ b = 0. We expand the eigenvalues and eigenfunctions **of** H [|l|] UZ **in** a series **in** ˜ b: E N,|l| ( ˜ b) = ∞� k=0 E N,|l| ˜k N,|l| k b , Ψ ( ˜b) = ∞� k=0 Ψ N,|l| ˜k k b and solve for the coefficients E N,|l| k , Ψ N,|l| k recursively. Here N **in**dexes the energy levels **of** H [|l|] UZ for fixed |l|. Aga**in** from the two-dimensional isotropic oscillator, the eigenfunctions **of** H [|l|] 0 are known exactly. The lowest state is non-degenerate, with eigenvalue and eigenfunction given by ⎛ ⎞ E 0,|l| 0 = |l|, Ψ0,|l| 0 = ⎝ r|l|−1 e −r2 /2 0 (5.3) ⎠ . (5.4) The rest **of** the states are two-fold degenerate, with eigenvalues and eigenfunctions given by ⎛ ⎞ Ψ N,|l| 0, up = Ψ N,|l| 0, dwn = ⎝ r|l|−1 L |l|−1 N (r2 )e −r2 /2 ⎛ ⎝ 0 0 r |l|+1 L |l|+1 N−1 (r2 )e −r2 /2 35 ⎠ , E N,|l| 0 ⎞ = 2N + |l|, ⎠ , N = 1,2, · · · (5.5)

- Page 1 and 2: A Born-Oppenheimer Expansion in a N
- Page 3 and 4: there exist quasimode energies of t
- Page 5 and 6: to both electronic states of the R-
- Page 7 and 8: 3 The Construction of the Quasimode
- Page 9 and 10: with eigenvalues ˜ E±(x, y) = ±
- Page 11 and 12: f ↔ g, Ψ1 ↔ Ψ2, h11 ↔ h22,
- Page 13 and 14: So we get E (1) = 0 and ψ (1) ⊥
- Page 15 and 16: and ⎛ Using what we know through
- Page 17 and 18: and ⎛ ⎝ f(k−2) g (k−2) ⎞
- Page 19 and 20: This easily follows from � �
- Page 21 and 22: H ± 1 = W −1 H ± 0 W = ⎛ ⎜
- Page 23 and 24: so that H2 = H0 + V . Note that for
- Page 25 and 26: Let β > 0. Then, � e 2γ〈x〉
- Page 27 and 28: � Proposition 4.7. Let Ψ = ≥ |
- Page 29 and 30: � = IR n \BS(t) � ≥ IR n \BS(
- Page 31 and 32: form (see Theorem XII.5 in [19])
- Page 33: Let r = a1/4 ρ, ˜b = b , and a HU
- Page 37 and 38: for the larger values of |l|. The s
- Page 39 and 40: 4 3.5 3 2.5 2 1.5 1 0.5 0 0 0.1 0.2
- Page 41 and 42: 1. For l �= 0, each +|l| state ge
- Page 43 and 44: Φ A ǫ is also asymptotic to an ei
- Page 45 and 46: We have (H(ǫ) − Eǫ,K)Φǫ,K = F
- Page 47 and 48: Acknowledgement It is a pleasure to