geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Reactivity of atomic cobalt with molecular oxygen: a combined IR matrix isolation and theoretical study of the formation and structure of CoO2


, : Reactivity of atomic cobalt with molecular oxygen: a combined IR matrix isolation and theoretical study of the formation and structure of CoO2. Journal of Physical Chemistry. A 109(1): 97-104

The reactivity of atomic cobalt toward molecular oxygen in rare gas matrices has been reinvestigated. Experiments confirm that Co atoms in their a(4)F ground state are inert toward O(2) in solid argon and neon but reactive in the b(4)F first excited state, in agreement with the previous gas-phase study of Honma and co-workers. The formation of CoO(2) starting from effusive beams of Co and O(2) has been followed by IR absorption spectroscopy, both in neon and argon matrices. Our observations show that only the dioxo form, OCoO, is stabilized in the matrix and that IR absorptions previously assigned to the peroxo and superoxo forms are due to other, larger species. The present data strongly support the linear geometry in rare gas matrices proposed by Weltner and co-workers. We report on measurements on all IR-active fundamental modes for (16)OCo(16)O, (18)OCo(18)O, and (16)OCo(18)O with additional combination transitions supplying anharmonicity correction. This allows for a 5.93 +/- 0.02 mdyne/A CoO harmonic bond force constant in solid neon. Using the empirical relationship previously optimized for the CoO diatomics, an approximate value for the CoO internuclear bond distance is proposed (1.615 +/- 0.01A). In light of recent theoretical studies predicting (2)A(1) or (6)A(1) electronic ground states, the geometry and electronic structure of the OCoO molecule has also been reconsidered. Calculations carried out at the CCSD(T)/6-311G(3df) level indicate a linear structure with an r(e) = 1.62 A bond distance, consistent with the experimental estimate. For later studies of larger systems, where CCSD(T) calculations become too time-consuming, an effective DFT-based method is proposed which reproduces the basic electronic and geometrical properties of cobalt dioxide. Quantitative results are compared to the experimental data and high-level results regarding bond length and frequencies. This DFT method is used to propose a reaction pathway.

US$19.90

PMID: 16839093

DOI: 10.1021/jp047327x


Other references

Anonymous, 2000: White shines bright. South African Mining, Coal, Gold and Base Minerals July: 10-11, 13

Shen, M.M.; Hodgkin, J., 1988: mab-3, a gene required for sex-specific yolk protein expression and a male-specific lineage in C. elegans. The gene mab-3 appears to regulate a subset of sex-specific events in C. elegans male development. Mutations in mab-3 have no apparent effect on hermaphrodites, but cause synthesis of yolk proteins and a limited lineage alteration in males. We inf...

Pogosiants, E.E., 1972: The main trends and tasks of genetics research in oncology. Voprosy Onkologii 18(8): 8-15

Bulens, A.; Van Beirendonck, S.; Van Thielen, J.; Buys, N.; Driessen, B., 2017: A two-level pen for fattening pigs: Effects on behavior, performance, and postslaughter measurements. Concurrent with a tendency toward higher slaughter weights of fattening pigs, minimum requirements for space allowance are increasing. Allowing pigs more space in existing standard pens, however, leads to a decrease in the number of pigs per pen,...

Edington, H.D.; Evans, S.; Sindelar, W.F., 1989: Reconstruction of a functional hemidiaphragm with use of omentum and latissimus dorsi flaps. After ablative surgery that involves the diaphragm, autologous tissue is the material of choice for reconstruction--particularly if adjuvant radiotherapy is planned. Latissimus dorsi muscle and omentum are reliable sources of such tissue. A case i...

Koistinen, P.; Siitonen, T.; Mantymaa, P.; Savolainen, E.R.itta, 2001: P53 and redox state in etoposide-induced acute myeloblastic leukemia cell death. We investigated whether p53, being a redox-sensitive protein, has a role in the responsiveness of AML cells to etoposide. Two subclones of the OCI/AML-2 cell line, the etoposide-sensitive (ES) and the etoposide-resistant (ER), were used as models....

Hanson, A.J., 1933: The potato flea beetles. In Washington there is one generation and a partial 2d generation annually. The overwintering adults emerge during May and June, adults of the new generation, July 25-August 17. They disappear by early November. Foliage injury increases with the p...

Honkala, S.M.; Motiani, K.K.; Eskelinen, J-Joonas.; Savolainen, A.; Saunavaara, V.; Virtanen, K.A.; Löyttyniemi, E.; Kapanen, J.; Knuuti, J.; Kalliokoski, K.K.; Hannukainen, J.C., 2017: Exercise Training Reduces Intrathoracic Fat Regardless of Defective Glucose Tolerance. Epicardial (EAT) and pericardial (PAT) fat masses and myocardial triglyceride content (MTC) are enlarged in obesity and insulin resistance. We studied whether the high-intensity interval training (HIIT) and moderate-intensity continuous training (...

Zhou, G.; Song, Z.; Yin, Y.; Jiang, W.; Wang, Z., 2016: Involvement of an alternative oxidase in the regulation of hyphal growth and microsclerotial formation in Nomuraea rileyi CQNr01. Mitochondria of Nomuraea rileyi contain an alternative oxidase (Aox), which reduces oxygen to water by accepting electrons directly from ubiquinol. Furthermore, through a transcriptional analysis, we found that an alternative oxidase (Nraox) was u...

Anand, S.; Stanifer, J.W.; Thomas, B., 2016: Clinical nephrology research in low-resource settings: opportunities, priorities, and challenges for young investigators. NlmCategory="UNASSIGNED">The increased recognition of the growing, worldwide burden of kidney disease has led to calls for prioritizing nephrology research in a global context. However, many challenges exist for young investigators in...