Transcript Fudemantal-7.pptx

An Overview of PNC Related Studies
Involving Heavy, Polar, Molecules
Timothy C. Steimle
Dept. Chem. & BioChem.,
Arizona State University, Tempe, AZ,USA
Funded by: NSF
The 68th International Symposium
on Molecular Spectroscopy, June 2013
The status of proposed and implemented eEDM experiments is well documented:
D M Kara, I J Smallman, J J Hudson, B E Sauer, M R Tarbutt and
E A Hinds New Journal of Physics 14 (2012) 103051
“Ref. A”
A. C. Vutha, W C Campbell, Y. V. Gurevich, N R Hutzler, M. Parsons, D. Patterson, E
Petrik, B. Spaun, J. M. Doyle, G. Gabrielse and D. DeMille J. Phys. B: At. Mol. Opt.
Phys. 43, 074007/1-9 (2010).
A.E. Leanhardt, J.L. Bohn, H. Loh, P. Maletinsky, E.R. Meyer, L.C. Sinclair, R.P. Stutz,
and E.A. Cornell, J. Mol. Spec. 270, 1-25, (2011)
YbF –Hind’s group (Imperial)
Talk # FD 11
PbO & ThO –DeMille’s (Yale) & Doyle’s (Harvard) groups
Talks # TF 06 and TF 15
HfF+ –Cornell’s group (U. Colorado)
Talks # TF 07 and 08
WC –Leanhart’s group (U. Michigan)
PbF –Shafer-Ray’s group (Okla)
Talk # TF 05
Commonality :Heavy, polar, radical molecules
a) “Heavy”-Relativistic effect (need high Z);
Also need unpaired e- in a penetrating orbital:
6p
WC:
..14s28p415s24(5d)16s(6s)
X3D1
Unpaired electrons on metal center.
HfF+:
..14s28p415s24(5d)16s(6s)
YbF:
ThO:
Yb+(f14s1)F-(2p6)
s =6s/6p hybrid
Th2+(f141s1)O2-(2p6)
a3D1
metastable
X2 S +
H3D1 metastable
s =7s/7p hybrid  =6d±2
All have unpaired electron in a “s” –s-type orbital
All orbitals with l >0 not as effective because centrifugal barrier prevents
penetration into area of nuclei.
b)”Polar”-Enhancement of electric field
What is
wanted
What is
needed
Polarization factor(0-1)
Meyer & Bohm Phys. Rev. A 78 (2008)
Eapp
M+
Eeff
x–
Complete polarization
results in largest
internal field Eint ;
For YbF: (Ref. A)
3D states
1
+
-
much easier to polarize:
Small -doubling
DE<1 MHz
1
Parity J
can only be obtained from theory. Requires accurate prediction of
 in region of nuclei.
Magnetic hyperfine parameters ( Fermi contact, bF & dipolar, c ) also
depend upon  in region of nuclei.
Hyperfine data
a. Test of Theory
bF & c (Exp.)
Talks # TF 09 and 11
Prof. Titov
bF & c (calc. using theory)
b. Semi-empirical prediction of based on experimental bF & c values
There are numerous other possible candidates, not necessarily diatomic
and not necessarily a “doublet” or a “triplet”. Consider IrF:
Large rel. effects
Ir
Ir+ (d7s1)
Ir+ (d8)
5F
5(E=0)
IrF:
3F (E=2260cm-1) IrF:
4
3,5Φ, 3,5Δ, 3,5Π, 3,5Σ3Φ, 3 Δ, 3Π, 3Σ-
3Φ
3Φ(d 8)
i –-
d 8+d7s1
i –-
d 8+d7s1
Spin-orbit
3Φ(d 7s1)
5Φ(d 7s1)
5Φ
3Φ
i –-
d 8+d7s1
IrF as an example
1) Two nuclear spin open shell molecule:
Atom
Abundance
(%)
gN
I
Mag.
(mN)
eQ.
(Barnes)
191Ir
37
0.101
3/2
0.151
0.82
193Ir
63
0.109
3/2
0.164
0.75
19F
100
5.376
1/2
2.629
_
2) The 19F magnetic hyperfine interaction is comparable to the
F1 is not an approximately good quantum number.
F1
F1
5.5
5.5
4.5
4.5
3.5
3.5
191,193Ir
magnetic hyperfine.
4
2.5
Rotation
Mag. (Ir)
3
2.5
[Mag.+Qua.] (Ir)
Will use these two
5 levels as an example
4 of how eEDM is
4 measured
3
J=4
X3Φ
F
6
5
hpfs(Ir)+hpf(F)
DE200 MHz
2
7
-8-
Optical spectrum know: LIF spectrum of IrF (1,0) A3Φ4-X3Φ4
Q Branch
Q4
R-Branch
P-branch
Q5
R5
Q5'
P5
P5'
R6
R4
Q6
P6'
Q4'
Q7
P9'
P7
P8
Q8
P7'
15916.8
15917.6
15918.4
15919.2
Wave number(cm-1)
R7'
Q6'
15921.0
15921.6
15922.2
15924.6
-1
15924.8
15925.0
Wave number(cm )
6s
68%
mel (mol) =2.86 D
g-factor  1 (same as YbF)
15925.2
-1
Wave number(cm )
Analysis of hyperfine
Analysis of Stark 
R8'
+R9'
Q7'
Q8'
P8'
15916.0
R8
+R9 R6'
R4'
P6
P9
R5' R7
+R10
15925.4
Possible e-EDM experiments (F=2 level IrF)
de0
+2
de0
-2
de0
DE1
-1
de0
+1
e
f
F=2
MF
E B
-2
-1
+1
de0
0
DE2
+1
-1
+2
de0
+2
de0
DE2 DE1
-2
de0
Relative magnitude of DE2 and DE1 switches when E is switched.
DE2-DE14(deEeff) < 10 mHz
r.f.
Pump
laser
E
Probe
laser
B
r.f.
F=3 xxxxxF=3 xxxxx
F=2xxxxx F=2xxxxx
p-r.f.
pulse
F=2
LIF
detection
xxxxx
xxxxx
-1
+1
+1
-1
0
F=3
p-r.f.
pulse
F=2xxxxx
F=3 xxxxx
F=2xx
Additional advantage of using polar molecules: Minimization of errors due to Bmot
Perpendicular to applied field
Produces a signal that mimics the eEDM ( Ref.A)
Matrix representation for Hstark +Hzee for in for F=2 of IrF (truncated)
MF
-2
MF -2
-1
0
-1
0
+1
+2
Bx off-diagonal
Bx effect minimized by making DStark large
+1
+2
Broader benefit of eEDM to related research areas
He-buffer beam sources:
Barry, J. F.; Shuman, E. S.; DeMille, D. A bright, slow, cryogenic
molecular beam source for free radicals. PCCP 2011, 13,
18936-18947.
Huztler, N.R.; Lu, H.-I.; Doyle, J.M. The Buffer Gas beam: An
Intense, Cold, and Slow Source for Atoms and Molecules. Chem.
Rev. 2012, 112, 4803-4827.
Stark deceleration
M. R.Tarbutt, H. L. Bethlem, J. J.Hudson, V. L.Ryabov, V. A.Ryzhov, B. E. Sauer, G. Meijer,
and E. A. Hinds Slowing Heavy, Ground-State Molecules using an Alternating Gradient
Decelerator” Phys. Rev. Lett. 92 173002/(2004).
Improved methods for relativistic ab initio and DFT
Generalized relativistic effective core potential (Titov and Skripnikov )
“Exact two component” (X2C) method (Gauss, Chang & Stanton)
RPPA and DFT methods (Schwerdtfeger)
Anapole moment (NSD-PV)
Hamiltonian operator:
D. DeMille, S.B. Cahn, D. Murphree,
D. A. Rahmlow and M.G. Kozlov, Phys.
Rev. Lett, 100, 023008, (2008).
Candidates:
137BaF 87SrF
Anapole moment constant
Proportional to size of nucleus2/3
227RaF
X2S+ 137BaF
N=1
G=2
G=1
G=2
N=0
G=1
Region of
interest
Spectroscopic data need for PV measurements
• Precise field-free energies
• Electronic spectroscopy (sensitive detection and
population manipulation)
• Franck-Condon Factors
• Permanent electric dipole moments- Stark tuning.
• Magnetic “g-factors”- Zeeman tuning.
• Magnetic hyperfine interactions-internal electric fields
Our Experiments: High Resolution Spectroscopy
Pump/Probe
Double
Optical
Zeeman
Optical
Starkresonance
spectroscopy
Spectroscopy
Horn
antenna
Stark
Helmholtz
coils
plates
Concluding remarks
• Numerous spectroscopic measurements are needed
PtH+, ThC, TlO, heavy polar polyatomic (e.g. dioxides)
Thank You!
Special thanks Joe Smallman and Ed Hinds (Imperial)