Novel silanetellones: Structures, ionization potentials, electron affinities, singlet–triplet gaps and Kohn–Sham HOMO–LUMO gaps of the X2SiTe and XYSiTe (X, Y=H, F, Cl, Br, I and CN) molecules

Novel germanetellones: XYGeTe (X, Y = H, F, Cl, Br, I and CN) – structures and energetics. Comparison with the first synthetic successes

“…For the X 2 GevTe (X = H, F, Cl, Br, I and CN) molecules, the predicted GevTe bond distances are in the order 2.335 Å (F) ≈ 2.336 Å (CN) < 2.339 Å (Cl) < 2.343 Å (Br) < 2.351 Å (I) < 2.356 Å (H) (MP2). The trend observed in the GevTe bond distance upon these substituent replacements is consistent with the literature for the corresponding substituted derivatives of telluroformaldehydes 20 and silanetellones 21 and the results are reported in Table ESI 1. † Another remarkable feature is that the X-Ge-Te bond angles are in the order 124.7°(H) < 126.3°( I) < 127.5°(Br) < 127.7°(CN) < 128.1°(Cl) < 130.4°(F).…”

“…7 also illustrates that the maximum IP ad(ZPVE) obtained for the dicyano-germanetellone derivatives are in good conformity with the literature for the analogous X 2 AvTe (A = C and Si; X = I and CN) systems. 20,21 Further, in most of the cases the ionization energies of these germanetellones are higher than those of the corresponding telluroformaldehyde derivatives. For instance, the energy required to remove an electron from I 2 CvTe is found to be 0.9 eV lower than that of I 2 GevTe.…”

“…The F-Ge-Te bond angle is found to be the largest, as predicted previously in the analogous cases of X 2 CvTe 20 and X 2 SivTe (X = F, Cl, Br, I and CN). 21 This can be rationalized in terms of the high electronegativity of fluorine, which decreases the electron density on the group 14 elements and hence increases the X-A-Te (A = C, Si and Ge) bond angles.…”

“…8, the electron affinities of the germanetellones studied vary as (NC) 2 GevTe < I 2 GevTe < Br 2 GevTe < Cl 2 GevTe ≈ F 2 GevTe < H 2 GevTe, as predicted analogously for X 2 CvTe 20 and X 2 SivTe (X = F, Cl, Br, I and CN). 21 Moreover, the EA ad(ZPVE) of the germanetellones are less than the corresponding telluroformaldehyde and silanetellone analogues. The lower the orbital energy of the π* LUMO, the more favorable is the addition of an extra electron into the molecular orbital and the larger is the EA value.…”

“…In light of this, we have previously reported the structures, ionization potentials, electron affinities and singlet-triplet gaps for the XYAvTe (A = C and Si; X, Y = H, F, Cl, Br, I and CN) molecules. 20,21 In addition, the energetic favorabilities of the unimolecular isomerization and decomposition reactions of the H 2 AvTe and HFAvTe (A = C, Si and Ge) molecules on their singlet state potential energy surfaces have been investigated. 22 Telluroformaldehyde, silanetellone, and germanetellone were found to be kinetically and thermodynamically more resistant to the unimolecular reactions explored than are the corresponding lighter chalcogen analogues.…”