Two isomers of CuO2: The Cu(O2) complex and the copper dioxide

Abstract

Photoelectron spectroscopy of CuO−2 has been studied at three detachment wavelengths: 532 nm, 355 nm, and 266 nm. Vibrationally resolved spectra for two distinct isomers are observed: the Cu(O2) complex and the copper dioxide molecule. The Cu(O)2 complex has an electron affinity (EA) of 1.503 (10) eV with a ground state vibrational frequency of 530 (50) cm−1. Its first electronic excited state is 7400 (300) cm−1 above the ground state. The Cu(O2)− anion is also observed to undergo photodissociation to Cu−+O2 at both 532 nm and 355 nm detachment wavelengths. The copper dioxide molecule is found to have a high EA of 3.46 (4) eV. Three low-lying excited states are observed within 1 eV above the ground state. The first two excited states of the copper dioxide molecule both possess a totally symmetric vibrational frequency of 640 (60) cm−1.

Characterization, Orbital Description, and Reactivity Patterns of Transition-Metal Oxo Species in the Gas Phase

“…This structural dichotomy needs to be kept in mind in the evaluation of the gas-phase properties of [M,O n ] +/o/) because more than a single isomer and/or state may be generated under the experimental conditions. In fact, coexistence of structural isomers has been demonstrated for anionic [69,88], neutral [89], cationic [84±86], and dicationic transition-metal oxides [85]. Unlike the monoxides, the electronic structures of transition-metal dioxides are more dif®cult to categorize because of bending, symmetry breaking, and the structural dichotomy mentioned above.…”

“…) and CuO À 2 anions has been demonstrated recently [88]. Considering the biochemical importance of copper in dioxygen activation, further studies of neutral and ionic copper oxides are anticipated.…”

Negative-ion photoelectron spectroscopy of Cu clusters reacted with NO molecules

“…However, few studies were devoted until recently to the electronic structures of the systems consisting of metal clusters and a molecule, which is regarded as a model of the molecule adsorbed on a metal surface. In recent years, negative-ion photoelectron spectroscopy, which is a powerful technique for studying the electronic structures of sizeselected neutral clusters, has been utilized for metal clusters reacted with simple adsorbates [16][17][18][19][20][21]. The extension of such studies is important so as to provide information about the number of the metal atoms contributing to adsorption, and thus to elucidate the adsorption mechanism on the bulk surface.…”

Density Functional Calculation of the Structure and Electronic Properties of Cu n O n (n=1-4) Clusters

“…Three isomers have been suggested as possible structures for CuO 2 [15]: bent CuOO (bent, C s ), linear OCuO, and C 2v OCuO. Evidence has been found both the bent CuOO [16,17,18,19] and the linear OCuO [15,20,21].…”

“…Three isomers have been suggested as possible structures for CuO 2 [15]: bent CuOO (bent, C s ), linear OCuO, and C 2v OCuO. Evidence has been found both the bent CuOO [16,17,18,19] and the linear OCuO [15,20,21]. Vibrational frequencies have been calculated [20] for CuO 3 [23] were determined using plane-wave density functional theory.…”