https://doi.org/10.1007/s10053-000-8810-4
Nuclear quadrupole hyperfine quantum beats in HCl and pyrimidine measured by the pump-probe method using REMPI/LIF detection
Physikalisch-Chemisches Institut der Universität Zürich,
Winterthurerstr. 190, 8057 Zürich, Switzerland
Received:
26
July
1999
Revised:
22
September
1999
Published online: 13 August 2013
Coherent time resolved IR-UV double resonance spectroscopy with REMPI
and/or LIF detection has been used to measure the nuclear hyperfine
structure of a diatomic and a polyatomic molecule. The pump-probe
technique was applied and the experimental set up was optimized to
achieve highest spectral resolution. Following excitation of the HCl
fundamental vibrational transition by a nanosecond IR laser pulse, the
nuclear quadrupole coupling constants were determined to be
MHz for H35Cl and
MHz for
H37Cl in the J=1 and J=2 states of the v=1 level.
Nuclear (Cl) spin-rotation interaction was shown to be active with the
corresponding coupling constant being
MHz for
H35Cl and
MHz for H37Cl. For pyrimidine a C-H
stretch vibration
was excited and the quadrupole tensor
elements for the rovibronic states
and 101 of
the
level were found to be
MHz,
MHz and
MHz. In this case
the residual frequency error was reduced to 8 kHz. The results of
these jet experiments independently confirm those from millimeter wave
and microwave measurements on static gas samples.
PACS: 42.50.Md – Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency / 33.15.Pw – Fine and hyperfine structure / 33.40.+f – Multiple resonances (including double and higher-order resonance processes, such as double nuclear magnetic resonance, electron double resonance, and microwave optical double resonance)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000