Juraj Varga - Prof. Per Jensen, Ph.D.
Juraj Varga - Prof. Per Jensen, Ph.D. Juraj Varga - Prof. Per Jensen, Ph.D.
Juraj Varga FSO 3 • radical measurements and improvements of our spectrometer QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk novská Dolina - Jasná, , Slovakia
- Page 2 and 3: Laboratory of High Resolution Molec
- Page 4 and 5: FSO 3 • radical ‣ the fluorosul
- Page 6 and 7: FSO 3 • radical 0.00004 intensity
- Page 8 and 9: FSO 3 • radical The simple Loomis
- Page 10 and 11: FSO 3 • radical The molecular par
- Page 12 and 13: Zeeman modulation Modulation freque
- Page 14 and 15: Laboratory of High Resolution Molec
<strong>Juraj</strong> <strong>Varga</strong><br />
FSO 3 • radical measurements and improvements of our spectrometer<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Laboratory of High Resolution Molecular Spectroscopy<br />
Prague<br />
‣ QUASAAR fellow from the 1 st January 2007 in the Laboratory of High Resolution Molecular<br />
Spectroscopy in Prague<br />
‣ research activities of the laboratory - high resolution spectroscopy in microwave spectral region<br />
of radicals and halogen containing molecules of an atmospheric importance i<br />
and their<br />
theoretical analysis → extremely accurate molecular structure and electrodynamical parameters<br />
‣ measurement of precise ground state rotational frequencies of stable molecules - CH 3 Br and<br />
radicals FCO 2 •,, FSO 3 •<br />
‣ L. Kolesniková, , J. <strong>Varga</strong>, H. Beckers, , M. Šimečková, , Z. Zelinger, , L. Nová Střítesk<br />
teská, , P. Kania, , H. Willner, and Š.<br />
Urban: Detailed study of fine and hyperfine structures in rotational spectra of the free fluoroformyloxyl radical<br />
FCO2, J. Chem. <strong>Ph</strong>ys. . 128, 1-8, 1<br />
(2008).<br />
‣ L. Kolesniková, , J. <strong>Varga</strong>, L. Nová Střítesk<br />
teská, , H. Beckers, , H. Wilner, , F. Aubke, and Š. . Urban: The Ground State<br />
Rotational Spectrum of the Fluorosulfate Radical, , J. Chem. <strong>Ph</strong>ys.,<br />
Accepted 2009.<br />
‣ improvement of measurements - development of the different modulation systems – Stark and<br />
Zeeman modulation<br />
‣ other experiments – multireflexion cell for weak transitions, Fabry-<strong>Per</strong>ot resonator for low<br />
frequencies (2-50 GHz)<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Laboratory of High Resolution Molecular Spectroscopy<br />
Prague<br />
The Prague millimeterwave spectrometer setup with the pyrolysis device for radical measurements.<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
‣ the fluorosulfate radical – open shell system with one unpair electron → primarily causes a fine<br />
splitting of the rotational levels into two sublevels – eletron spin-rotational interaction<br />
‣ magnetic hyperfine interactions between the magnetic moments of the open shell electron<br />
system and the 19 F nucleus as well as nuclear spin-rotational interaction → additional hyperfine<br />
doubling of levels – very small, in rotational spectra nearly unresolved<br />
‣ radical was produced by a low pressure pyrolysis of the bis(fluorosulfuryl)peroxide (430 K,<br />
sample pressure of the equilibrium mixture was 6 ubar)<br />
FSO 2 O-OSOOSO 2 F ↔ 2 FSO3•<br />
‣ measurements spectral range – 93-281 GHz, frequency modulation with the second harmonic<br />
lock-in detection<br />
‣ measured in its vibronic ground state, more than 250 fine rotational transitions have been<br />
en<br />
observed, analyzed in detail using the matrix elements of the rotational, fine and hyperfine<br />
Hamiltonian terms – observed, identified and analyzed for the first time<br />
‣ derived very precise values of the rotational, centrifugal distorsion and fine constants and the<br />
C 3v molecular symetry of the vibronic ground state was unambigously confirmed<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
0.0007<br />
0.0006<br />
0.0005<br />
0.0004<br />
0.0003<br />
intensity [a.u.]<br />
0.0002<br />
0.0001<br />
0.0000<br />
-0.0001<br />
-0.0002<br />
-0.0003<br />
-0.0004<br />
-0.0005<br />
270000 272000 274000 276000 278000 280000<br />
frequency [MHz]<br />
10 GHz overview with 150 MHz step – ~ 1000 lines, ~ 30 belongs to FSO3• radical<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
0.00004<br />
intensity [a.u.]<br />
0.00000<br />
269970 270000 270030<br />
frequency [MHz]<br />
Example of the spectrum of fluorosulfate radical rotational transition N’ ← N” =26← 25<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
The radical and nonradical spectra measured with and without the magnetic field: a) the radical<br />
lines are broadened and their peak heights are decreased because of the molecular Zeeman<br />
Effect; b) the lines of the closed shell molecules are unaffected by the magnetic field and both the<br />
spectrum traces are completely overlapped<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
The simple Loomis–Wood diagram indicates the assignments of the radical transition lines to rotational and<br />
electron spin quantum numbers. The two groups of points for a given upper N’ quantum number correspond to<br />
different values of ms = ±½ and thus to different components of the fine splitting. For some of these groups, the<br />
highest possible K values are indicated.<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
The parts of the radical spectrum with transitions from energy<br />
levels with the quantum numbers N” = 19 in the vibronic ground<br />
state corresponding to the row with N’ = 20 of the Loomis–Wood<br />
diagram<br />
An illustration of the resolved hyperfine<br />
splitting in the fluorosulfate radical rotational<br />
transition N’ ← N” =10← 9.<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
FSO 3<br />
• radical<br />
The molecular parameters of the fluorosulfate radical in the vibronic ground state a,b,c .<br />
Parameter<br />
without hyperfine splitting<br />
with hyperfine splitting<br />
B<br />
5195.528365 (259)<br />
5195.528364 (291)<br />
D N<br />
×10 3 3.76291 (60)<br />
3.76287 (64)<br />
D NK<br />
×10 3 −1.28189 (131)<br />
−1.28162 (183)<br />
H N<br />
×10 9 −6.75 (44)<br />
−6.83 (46)<br />
H NK<br />
×10 6 0.18816 (127)<br />
0.18872 (156)<br />
H KN<br />
×10 6 −0.34627 (194)<br />
−0.34765 (307)<br />
h 3<br />
×10 9 6.640 (21) b<br />
6.640 (21) b<br />
ε aa<br />
−37.372 (59)<br />
−37.344 (67)<br />
ε bb<br />
−271.9178 (189)<br />
−271.8446 (265)<br />
D S N ×103 −0.9931 (73)<br />
−1.0123 (90)<br />
D S NK<br />
−0.0696 (188)<br />
−0.0616 (228)<br />
D S KN<br />
0.0725 (190)<br />
0.0646 (230)<br />
D S K ×103 −1.628 (275)<br />
−1.58 (37)<br />
a F<br />
…<br />
−24.1 (45)<br />
1.5 T aa<br />
…<br />
−2.628 (288)<br />
s c 0.014<br />
0.014<br />
a All the data are in MHz. The numbers in parentheses<br />
are standard deviations in the units of the last decimal<br />
digit. The frequencies of the K = 3 doublets are<br />
averaged.<br />
b Fitted separately.<br />
c The symbol s denotes a standard deviation of the fit.<br />
‣L.<br />
Kolesniková, , J. <strong>Varga</strong>, L. Nová Střítesk<br />
teská, , H. Beckers, , H.<br />
Wilner, , F. Aubke, and Š. . Urban: The Ground State Rotational<br />
Spectrum of the Fluorosulfate Radical, , J. Chem. <strong>Ph</strong>ys.,<br />
Accepted 2009.<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Stark modulation<br />
f [kHz]<br />
U in [V]<br />
1<br />
2<br />
4<br />
6<br />
8<br />
10<br />
12<br />
14<br />
16<br />
18<br />
20<br />
22<br />
24<br />
26<br />
28<br />
30<br />
32<br />
34<br />
36<br />
38<br />
40<br />
44<br />
46<br />
50<br />
3150<br />
3100<br />
3050<br />
3000<br />
2900<br />
2740<br />
2600<br />
2450<br />
2400<br />
2400<br />
2400<br />
2400<br />
2370<br />
2350<br />
2200<br />
1800<br />
1250<br />
1100<br />
1075<br />
1000<br />
1000<br />
1000<br />
1000<br />
975<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Zeeman modulation<br />
Modulation frequency 0.5 – 3 kHz, magnetic field 4 mT<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Acknowledgement<br />
‣ Marie Curie Research Training Network (QUASAAR)<br />
‣ <strong>Prof</strong>. RNDr. Štěpán Urban, CSc. as my supervisor<br />
‣ all collaborating laboratories: Wuppertal - prof. Willner group, CTU Prague<br />
QUASAAR Winter School, February 20-25, 25, 2009 Demänovsk<br />
novská Dolina - Jasná, , Slovakia
Laboratory of High Resolution Molecular Spectroscopy<br />
Prague<br />
<strong>Prof</strong>. RNDr. Štěpán Urban, CSc.<br />
Ing. Lucie Nová – Stříteská, <strong>Ph</strong>D.<br />
Ing. Lucie Kolesníková<br />
Ing. Patrik Kania, <strong>Ph</strong>D.<br />
Ing. Jindřich Koubek<br />
Michal Rybníček<br />
Mgr. Tereza Uhlíková, <strong>Ph</strong>D.<br />
juraj.varga@vscht.cz<br />
http://www.vscht.cz/anl/lmsvr/
Thank you for your attention.