Hokotomo Inouye

Repulsive potentials for Cl−–R and Br−–R (R=He, Ne, and Ar) derived from beam experiments

Repulsive potentials for Cl−–R and Br−–R (R=He, Ne, and Ar) have been derived from the experimental values of integral scattering cross sections of the ions in the energy range 0.5–4 keV. The potentials are well represented by an exponential form, V (R) =A exp(−αR). The numerical values of the parameters, A (eV) and α (A−1), are as follows: Cl−–He, 255, 2.88; Cl−–Ne, 820, 3.05; Cl−–Ar, 1470, 3.01; Br−–He, 365, 2.92; Br−–Ne, 985, 3.05; and Br−–Ar, 1420, 2.83. The potential parameters are found to be closely related to the electronic charge distributions in the colliding pairs on the assumption of overlapping of the electron clouds.

Elastic Scattering of Li+ Ions in Helium

Repulsive potentials between a Li+ ion and a He atom have been derived from the experimental values of integral elastic scattering cross sections of the ions in the energy range of 500–4000 eV. The potentials are well represented by the following analytical expression: V(r)=428 exp(−5.11r), 0.78≤ r≤ 1.21, where V(r) is in units of eV and r in angstroms.

Experimental Determination of the Repulsive Potentials between K+ Ions and Rare‐Gas Atoms

Integral elastic scattering cross sections have been measured by the attenuation method for potassium ions with an energy selected in the range of 500–4000 eV scattered by room‐temperature He, Ne, Ar, and Kr atoms through effective laboratory angles greater than 5×10−3 rad. The repulsive potentials have been derived from the measured values of the cross sections with allowance for the density distribution across the beam in the collision chamber. The potentials are well represented by the following expressions: He:    V(r) = 1110 exp(−4.15r)    for    1.23 < r < 1.77,Ne:    V(r) = 4910 exp(−4.40r)    for    1.55 < r < 2.04,Ar:    V(r) = 2920 exp(−3.46r)    for    1.79 < r < 2.43, and Kr:    V(r) = 6420 exp(−3.69r)    for    1.92 < r < 1.53, where V(r) is in electron volts and r in angstroms.

Repulsive potentials for Na+–R and Al+–R (R= rare gas atoms) derived from beam experiments

Repulsive potentials for Na+–R and Al+–R (R=rare gas atoms) are derived from integral scattering experiments using the projectile ions in the energy range 0.5–4 keV. The potentials are well represented by an exponential formula, V (R) =A exp(−αR). The numerical values of the parameters, A (eV) and α (A−1), are Na+–He, 1200, 4.92; Na+–Ne, 5350, 5.12; Na+–Ar, 11 340, 4.68; Na+–Kr, 9600, 4.33; Al+–He, 325, 3.50; Al+–Ne, 1220, 3.93; and Al+–Ar, 3170, 3.86. The statistical computation published by Kim and Gordon [J. Chem. Phys. 60, 4323 (1974)] for Na+–R is in good agreement with the experiments, and the values for Al+–He and Al+–Ar computed by a similar statistical method are also in good agreement with the experimental results, while Al+–Ne resulted in a significant discrepancy.

Experimental determination of repulsive potentials between alkali ions (Li+, Na+, and K+) and N2 and CO molecules

Abstract Integral scattering cross sections have been measured for alkali ions (Li + , Na + and K + ) in the energy range 500–4000 eV scattered by room temperature N 2 and CO molecules through effective laboratory angles greater than 5 × 10 −3 rad. The repulsive potentials deduced from the cross sections are represented bya practically identical formula for the Na + N 2 and Na + CO systems, and for the K + CO systems, respectively, while the repulsive potentials of the Li + N 2 system are somewhat smaller than those of the Li + CO system at larger intermolecular distances.

Valence full configuration interaction calculation of the CN+ ion

Abstract Ab initio valence full configuration interaction calculations for some low-lying electronic states of CN + have been carried out at five internuclear distances between 2.2 and 2.95 au and the potential energy curves for the states are obtained from the results. A minimal basis set of Slater type orbitals has been used. For singlet states, the calculated spectroscopic constants are compared with the experimental ones. The agreement between the calculated and observed results is satisfactory. Our spectroscopic constants of the triplet states are the first to be published. Avoided crossings in the potential energy curves of the f 1 Σ + and 3 Σ + II states appear as humps around an internuclear distance of about 1.5 A. The calculated results suggest that the a 1 Σ + state is the ground state, but this is not conclusive.

Repulsive potentials derived from beam scattering of Rb+ and Cs+ ions by rare gas atoms

Integral cross sections of elastic scattering through effective LAB angles greater than 5×10−3 rad have been measured for collisions of Rb+ and Cs+ ions in the LAB energy range 500–4000 eV with room temperature rare gas atoms (He through Xe). Repulsive potentials in the range 0.5–10 eV derived from the results for the ion–atom pairs can be all expressed by exponential formulas. The potentials for Rb+–Ar, –Kr, and –Xe are in excellent agreement with the results derived from the mobility experiments by Gatland et al., but agreement between the two experiments for Cs+–Ar, –Kr, and –Xe are poor. The potential values calculated by Ishikawa et al. on the basis of the Gordon–Kim electron gas model are generally 20%–25% lower than the results of the present work.

Experimental determination of repulsive potentials between alkali ions (Li+, K+, and Cs+) and hydrogen molecules (H2 and D2)

Integral elastic scattering cross sections of alkali ions (Li+, K+, and Cs+) in collision with room temperature hydrogen molecules (H2 and D2) were measured in the ion energy range 500–4000 eV. Some difference in the cross sections due to the replacement of the target gases were found in K+‐ and Cs+‐hydrogen systems. Most of the difference can be explained by the difference of the target masses. The repulsive potentials deduced from the cross sections in a usual manner are represented by the following formulas independently of the isotopes: Li+: V(R) = 345 exp(−4.31 R), 0.88 < R < 1.43; K+: V(R) = 810 exp(−3.52 R), 1.33 < R < 1.98; and Cs+: V(R) = 1110 exp(− 3.26 R), 1.55 < R < 2.25; where V(R) is in units of electron volts and R in angstroms.

Experimental Determination of the Repulsive Potentials between Li^+ Ions and Rate-Gas Atoms

Integral elastic scattering cross sections of Li + ions scattered through effective laboratory angles greater than 5×10 -3 rad in collision with Ne, Ar, and Kr atoms at room temperatures were measured in the ion energy range of 500–4000 eV. The repulsive potentials derived from the cross sections are represented by the following analytical formulas:

Rainbow effects and momentum transfer mechanisms in collisions of Na+ ions with N2 and CO molecules

Rotational and vibrational excitations of molecules in Na+-N2 and Na+-CO collisions were studied at centre-of-mass energies of 27<or=E<or=192 eV. The energy of the scattered particles was analysed by a time-of-flight technique. The energy-loss spectra of the ions scattered in Na+-N2 collisions contain two peaks, while those for Na+-CO contain three peaks. The structures in the spectra can be well explained by rainbow effects arising from rotational and vibrational excitation.