MRCI study of the photoelectron spectrum of GeC and GeSi and their GeC⁺ and GeSi⁺ ions

Abstract

ABSTRACT:The lowest-lying states of the species GeC, GeC ϩ , GeSi, and GeSi ϩ were studied using the multireference configuration interaction (MRCI) method and the aug-cc-pVQZ basis set. For the first time, the GeC ϩ molecule was characterized. The dissociation energy (D 0 ) of the ground state (X 3 ͟) of GeC is equal to 3.70 eV, showing good agreement with the theoretical result (3.90 eV) of Sari and colleagues. These results, however, are considerably smaller than the experimental value of 4.72 eV. The dissociation energy of the ground state (X 3 ¥ Ϫ

Electronic states and spectroscopic properties of GeSi

“…The computed ground-state bond length of GeSi is 0.017 Å shorter than the value reported by Sefyani and co-workers [26,27]. However, the present r e value is closer to the MRCI estimated value of Ueno et al [29], while the local spin-density calculations [25] reported a value of 2.3389 Å. The highly correlated coupled-cluster calculations [28] predicted r e = 2.3114 Å for the ground state at the Rel-aug-cc-pVQZ CCSD(T) level.…”

“…A large discrepancy of about 18 kcal/mol has been reported between the theoretical and experimental dissociation energy of GeC. Very recently, the lowest few states of GeC, GeSi, and their monopositive ions have been theoretically investigated by Ueno et al [29]. They have used the MRCI method and the augmented correlation-consistent polarized valence quadruple zeta type of basis functions.…”

The dissociation energy of the new diatomic molecules SiPb and GePb

“…51 The GeSi species was also studied more recently by high level calculations. [52][53][54] At the highest level of the calculations performed here, CCSD͑T͒ with a triple zeta augmented basis set, the equilibrium distance and harmonic vibrational frequency of the Pb 2 ground state are predicted to be 2.865 Å and 139 cm −1 , respectively, as compared to the experimental values of 2.9271 Å ͑Refs. 42 and 43͒ and ͑110± 15͒ cm −1 .…”

Observation of Aromatic Three-Membered Rings in Ge3C and Ge3O via Photoelectron Spectroscopy and Theoretical Calculations

“…Doping with other elements (such as C and O) has been proved to be effective for improving its cycling performance. It has been reported that the germanium–carbon nanocomposites and the amorphous porous GeO x nanomaterials exhibit highly reversible Li storage behavior and superior rate capability. − In the last decades, immense effort has been devoted to study the binary Ge–C clusters − and Ge–O clusters − by theoretical calculations and by a number of experimental techniques such as Raman spectroscopy, infrared spectroscopy, mass spectroscopy, microwave spectroscopy, rotational spectroscopy, and photoelectron spectroscopy. The structure of Ge 3 C was investigated using the Knudsen effusion mass spectroscopy and the density functional theory (DFT) calculations .…”