A combined ab initio and Franck–Condon factor simulation study on the photodetachment spectrum of HfO2−

Abstract

Restricted-spin coupled-cluster single-double plus perturbative triple excitation {RCCSD(T)} potential energy functions (PEFs) of the X[combining tilde]1A1 state of HfO2 and the X[combining tilde]2A1 state of HfO2- were computed, employing the quasi-relativistic effective core potential, ECP60MWB, and an associated contracted [13s6p6d4f3g2h] basis set designed for Hf, and the augmented correlation-consistent polarized valence quadruple-zeta (aug-cc-pVQZ) basis set for O. Based on the differences between the computed r0 and re geometrical parameters obtained from the PEF, and available experimentally derived r0 geometrical parameters of the X[combining tilde]1A1 state of HfO2, the experimental re geometrical parameters of the X[combining tilde]1A1 state of HfO2 were estimated as:-re(HfO)=1.7751 A and thetae(OHfO)=107.37 degrees. In addition, Franck-Condon factors for the HfO2 (X[combining tilde]1A1)+e<--HfO2- (X[combining tilde]2A1) electron detachment process, which include allowance for Duschinsky rotation and anharmonicity, were calculated using the computed RCCSD(T) PEFs, and were used to simulate the HfO2 (X[combining tilde]1A1)+e<--HfO2- (X[combining tilde]2A1) photodetachment band of HfO2-. Employing the estimated experimental re geometrical parameters of the X[combining tilde]1A1 state of HfO2 obtained in this work, the iterative Franck-Condon analysis (IFCA) procedure was carried out to optimize the geometrical parameters of the X[combining tilde]2A1 state of HfO2- until the simulated spectrum matched best with the experimental 355 nm photodetachment spectrum of W. Zheng, et. al., J. Phys. Chem. A, 1998, 102, 9129. The equilibrium geometrical parameters of X[combining tilde]2A1 state of HfO2- derived via the IFCA procedure are re(HfO)=1.823 A and thetae(OHfO)=111.5 degrees. Further calculations on low-lying triplet states of HfO2 gave adiabatic electronic energies (Te's) of, and vertical excitation energies (Tvert's) to, the ã 3B2, b[combining tilde]3B1, c[combining tilde]3A1 and d[combining tilde]3A2 states of HfO2 (from the X[combining tilde]1A1 state of HfO2), as well as electron affinities (EAs) and vertical detachment energies (VDEs) to these neutral states from the X[combining tilde]2A1 state of HfO2-.

Unveiling the Coexistence of Cis and Trans Isomers in the Hydrolysis of ZrO2: A Coupled DFT and High-Resolution Photoelectron Spectroscopy Study

“…S1 in the SI for the full overview spectrum. These highresolution traces highlight structure covering eBEs from 9,300 to 10,000 cm −1 , revealing a number 3 as well as the target 90 ZrO 3 H − 2 species; the electron affinity of ZrO 3 has not been experimentally determined, but is calculated to be 3.06 eV, substantially higher than the photon energies employed in this work (<1.35 eV), and thus should not contribute to the reported spectra.…”

“…Bare (ZrO 2 ) 0/n clusters have been extensively studied using PES, [81][82][83] matrix-IR spectroscopy, [84] Fourier-transform microwave spectroscopy, [85] laser-induced fluorescence, [86] resonant multiphoton ionization, [86] dispersed fluorescence, [86] and computational methods. [81,84,[87][88][89][90] Despite this growing body of work, there is no experimental data on the reactions of these clusters with a water molecule, though computational studies by Dixon et al [91] on the (ZrO 2 ) n + H 2 O (n=1-4) reaction find these clusters are capable of splitting water. That work shows the dissociative adduct to be more stable than the molecularly adsorbed species by roughly 200 kJ/mol, at both the DFT and coupled cluster levels of theory, in agreement with experimental observations on bulk zirconia.…”

The low-lying singlet electronic excited states of ZrO2: A symmetry adapted cluster–configuration interaction (SAC–CI) study

“…Compared with studies on the TiO 2 molecule, fewer studies have focused on the ZrO 2 molecule [1][2][3][4][5][6][7]. The Fourier transform microwave spectroscopy of ZrO 2 was conducted; the Zr-O bond length, O-Zr-O bond angle, and electric dipole moment of the ground electronic state (X 1 A 1 )…”

Simulated photodetachment spectra of AlH2−

“…This procedure has been used successfully to assign the photodetachment spectra of several triatomic negative ions. [14][15][16][17][18] However, as will be shown below, comparison between simulated and experimental spectra suggests that the experimental spectrum assigned to AlH 2 − in Ref. 1 is unlikely to be due to AlH 2…”