Rydberg states of the ArCO2 and KrCO2 van der Waals molecules
- Argonne National Lab. (ANL), Argonne, IL (United States)
Relative photoionization cross sections were determined for ArCO2 at a wavelength resolution of 0.24 A in the regions of both the Ar*+CO2 and the Ar+CO2* dissociation limits (690--920 Â) and for KrCO2 at a wavelength resolution of 0.4 Â in the region of the Kr+CO2* dissociation limits (690--780 Â). The dimer ionization potentials are 13.59±0.04 eV (912.5±2.5 Â) for ArCO2 and 13.33±0.04 eV (930.0±3.0 Â) for KrCO2. Combining these values with the known value of the CO2 ionization potential and the known (or estimated) values of the ArCO2 and KrCO2 dissociation energies yields values for the dimer ion ground state dissociation energies of 0.20±0.04 eV for ArCO2⁺ and 0.47±0.05 eV for KrCO2⁺. Rydberg structure is observed in the photoionization cross section of ArCO2 corresponding to dissociation limits of the type Ar*(nd,ns)+CO2; however, discrete structure is observed only near the Ar*(3d,5s)+CO2 dissociation limits. Van der Waals structure corresponding to the higher Ar*+CO2 limits is diffuse and red degraded. Molecular Rydberg structure also is observed in the photoionization cross sections of both ArCO2 and KrCO2 corresponding to dissociation limits of the type Ar+CO2*. Prominent van der Waals structure is observed corresponding to dissociation limits based on members of the CO2 Henning sharp and diffuse Rydberg series, which converge to CO2⁺ B ²Σu⁺ ; however, no van der Waals structure is observed corresponding to dissociation limits based on members of the CO2 Tanaka–Ogawa Rydberg series, which converge to CO2⁺ A ²Πu . Various experimental evidence indicates that neither vibrational predissociation of the excited van der Waals dimer nor vibrational predissociation of the dimer ion can account completely for the absence of van der Waals structure corresponding to the Tanaka–Ogawa series in CO2.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE; US Department of the Navy, Office of Naval Research (ONR)
- DOE Contract Number:
- W-31-109-ENG-38
- OSTI ID:
- 5646372
- Journal Information:
- Journal of Chemical Physics, Vol. 83, Issue 1; ISSN 0021-9606: JCPSA6
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Photoionization studies of the diatomic heteronuclear rare gas molecules XeKr, XeAr, and KrAr
Molecular photoionization studies
Related Subjects
ARGON
ADDUCTS
ARGON COMPOUNDS
PHOTOIONIZATION
RYDBERG STATES
CARBON DIOXIDE
KRYPTON
KRYPTON COMPOUNDS
CROSS SECTIONS
VAN DER WAALS FORCES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
IONIZATION
NONMETALS
OXIDES
OXYGEN COMPOUNDS
RARE GAS COMPOUNDS
RARE GASES
640302* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Properties & Theory