Radiation characteristics of diatomic molecules

Halogenated silanes, radicals, and cations: Theoretical predictions on ionization energies, structures and potential energy surfaces of cations, proton affinities, and enthalpies of formation

“…Using mass-selected photoionization efficiency spectroscopy, Marijnissen et al obtained a much precise value of 7.3296 ± 0.0014 eV [35], which is supported by our G3(CC) prediction of 7.34 eV and by previous CCSD(T)/aug-cc-pVQZ prediction of 7.30 eV [51]. For SiBr, Bosser et al [33] and Kuznetsova et al [37] reported IE a of 6.67 and 7.3 eV from Rydberg spectroscopy. The large error in IE a (SiCl) by Bosser Ground states of silylene radicals are singlet, even though RHFwavefunction instability is found for these radicals except for SiF 2 .…”

“…Present G3(CC) represents the first systematic study on this system. G3(CC) calculations show strong effects from F-substitution with increased IE a from SiH 2 F (8.12 eV) to SiF 3 (9.17 eV), very small effect from Cl- Values are obtained from: a JANAF table [94]; b photoionization [31]; c Ion chemistry [38]; d BAC-MP4/6-31G(d,p) [29]; e Ion chemistry [40]; f Ion chemistry [41]; g Rydberg series [32]; h CCSD(T)/CBS [54]; i Ion chemistry [43]; j Ion chemistry [44]; k Rydberg series [33]; l Photoionization mass spectrometry [35]; m CCSD(T)/AVQZ calculation [51]; n Electron impact ionization [76]; o Rydberg series [37]; p Photoelectron spectroscopy [72]; q CCSD(T)/CBS [60]; r Electron impact ionization [73]; s Photoelectron spectroscopy [74]; t G2(MP2) calculation [51]; u Estimation from photoionization [75]; v Rydberg series [36]; w Photoelectron spectroscopy [78]; x Ion-molecule reaction [45,46]; y Estimation from photoelectron spectroscopy [77]. substitution with small change of IE a from SiH 2 Cl (7.90 eV) to SiCl 3 (7.85 eV), and from Br-substitution with slightly decreased IE a from SiH 2 Br (7.83 eV) to SiBr 3 (7.63 eV).…”

“…Reliable measurements on IE a were available only to SiH x 0,+1 (x = 1-4) from photoionization mass spectrometry study by Berkowitz et al [31]. There were also reports on IE a (SiX, X = F,Cl,Br) from photoionization efficiency spectroscopy or VUV spectroscopy of Rydberg states [32][33][34][35][36][37].…”

Semiclassical and quantum-mechanical descriptions of S2molecular radiation

“…where σ sym is a statistical symmetry factor that equals 1 for heterogeneous and 1 2 for homogeneous molecules. Since this factor also appears in Z, it effectively cancels in equation (14). It is, however, of importance for the absolute value of Z.…”

“…Figure 4 shows the sulfur potential curves (states X and B) that have been taken into account [14,15], along with the light wavelength as a function of radius according to the FCP. First, we calculate the S 2 partition functions using equations ( 25) and ( 9) to verify that the quantum-mechanical and semiclassical methods give numerically similar results.…”