Publications by authors named "Gennady L Gutsev"

19 Publications

  • Page 1 of 1

The Concentration of C() Atoms and Properties of an Activated Carbon with over 3000 m/g BET Surface Area.

Nanomaterials (Basel) 2021 May 17;11(5). Epub 2021 May 17.

Department of Physics, Florida A&M University, Tallahassee, FL 32307, USA.

The alkaline activation of a carbonized graphene oxide/dextrin mixture yielded a carbon-based nanoscale material (AC-TR) with a unique highly porous structure. The BET-estimated specific surface area of the material is 3167 m/g, which is higher than the specific surface area of a graphene layer. The material has a density of 0.34 g/cm and electrical resistivity of 0.25 Ω·cm and its properties were studied using the elemental analysis, transmission electron microscopy (TEM), electron diffraction (ED), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray induced Auger electron spectroscopy (XAES), and electron energy loss spectroscopy (EELS) in the plasmon excitation range. From these data, we derive an integral understanding of the structure of this material. The concentration of carbon atoms was found to be relatively low with an absolute value that depends on the measurement method. It was shown that there is no graphite-like (002) peak in the electron and X-ray diffraction pattern. The characteristic size of a -domain in the basal plane estimated from the Raman spectra was 7 nm. It was also found that plasmon peaks in the EELS spectrum of AC-TR are downshifted compared to those of graphite.
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http://dx.doi.org/10.3390/nano11051324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8156701PMC
May 2021

Superhalogens Among 3-Metal Compounds: F, F, F, and F ( = Sc-Zn).

J Phys Chem A 2021 May 12;125(20):4409-4419. Epub 2021 May 12.

Institute for Micromanufacturing, Louisiana Tech University, Ruston, Louisiana 71272, United States.

The ground states of the neutral and anionic tetrafluoride and hexafluoride series of 3-metal atoms from Sc to Zn were assigned by using a double-check approach in which the pure and hybrid density functional methods were interchangeably used. It was confirmed that all these neutral fluorides are superhalogens except for TiF. The electron affinities of the hexafluorides were shown to be consistently higher than those of the tetrafluorides in accordance with the superhalogen conception of the extra electron delocalization over a larger number of the electronegative ligands. In the search for mononuclear fluorides possessing higher electron affinities, we considered the (F) and (F) series where = Sc-Zn. We found that the optimized geometrical structures in both series may be described as F- (F), = 3 and 6, of which the geometry of the F core mimics that of the corresponding hexafluoride anion and the F dimers are kept in a bound state by polarizing forces. In these cases, the electron affinity is decreased by tenths of eV with respect to the electron affinity of the core hexafluorides due to a confinement of the extra electron by the F environment.
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http://dx.doi.org/10.1021/acs.jpca.1c02884DOI Listing
May 2021

Dissociation of dinitrogen on iron clusters: a detailed study of the Fe + N case.

Phys Chem Chem Phys 2021 Jan;23(3):2166-2178

Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.

The coalescence of two Fe8N as well as the structure of the Fe16N2 cluster were studied using density functional theory with the generalized gradient approximation and a basis set of triple-zeta quality. It was found that the coalescence may proceed without an energy barrier and that the geometrical structures of the resulting clusters depend strongly on the mutual orientations of the initial moieties. The dissociation of N2 is energetically favorable on Fe16, and the nitrogen atoms share the same Fe atom in the lowest energy state of the Fe16N2 species. The attachment of two nitrogen atoms leads to a decrease in the total spin magnetic moment of the ground-state Fe16 host by 6 μB due to the peculiarities of chemical bonding in the magnetic clusters. In order to gain insight into the dependence of properties on charge and to estimate the bonding energies of both N atoms, we performed optimizations of Fe16N and the singly charged ions of both Fe16N2 and Fe16N. It was found that the electronic properties of the Fe16N2 cluster, such as electron affinity and ionization energy, do not appreciably depend on the attachment of nitrogen atoms but that the average binding energy per atom changes significantly. The lowering in total energy due to the attachment of two N atoms was found to be nearly independent of charge. The IR and Raman spectra were simulated for Fe16N2 and its ions, and it was found that the positions of the most intense peaks in the IR spectra strongly depend on charge and therefore present fingerprints of the charged states. The chemical bonding in the ground-state Fe16N20,±1 species was described in terms of the localized molecular orbitals.
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http://dx.doi.org/10.1039/d0cp05427eDOI Listing
January 2021

Reduced Graphene Oxide Aerogel inside Melamine Sponge as an Electrocatalyst for the Oxygen Reduction Reaction.

Materials (Basel) 2021 Jan 9;14(2). Epub 2021 Jan 9.

Department of Physics, Florida A&M University, Tallahassee, FL 32307, USA.

A graphene oxide aerogel (GOA) was formed inside a melamine sponge (MS) framework. After reduction with hydrazine at 60 °C, the electrical conductive nitrogen-enriched rGOA-MS composite material with a specific density of 20.1 mg/cm was used to fabricate an electrode, which proved to be a promising electrocatalyst for the oxygen reduction reaction. The rGOA-MS composite material was characterized by elemental analysis, scanning electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. It was found that nitrogen in the material is presented by different types with the maximum concentration of pyrrole-like nitrogen. By using Raman scattering it was established that the rGOA component of the material is graphene-like carbon with an average size of the sp-domains of 5.7 nm. This explains a quite high conductivity of the composite obtained.
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http://dx.doi.org/10.3390/ma14020322DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7827904PMC
January 2021

Influence of back donation effects on the structure of ZnO nanoclusters.

J Comput Chem 2020 Nov 21;41(30):2583-2590. Epub 2020 Sep 21.

Department of Physics, Florida A&M University, Tallahassee, Florida, USA.

The structure and properties of ZnO quantum dots is a very popular and rapidly growing field of research for which accurate quantum calculations are challenging to perform. Since the dependence between system size and wall time scales nonlinearly, certain compromises have to be made. A particularly important limiting factor is the size of the basis used, this is especially the case if accurate large calculations are to be carried out. In our work, we discovered that an important O(2p)->Zn(4p) back donation, which greatly influences the strength of the ZnO bond, can be reproduced only if diffuse functions are added to the basis set. We further tested the basis dependence for the magic-sized wurtzite nanophase ZnO clusters which were previously shown to be able to accurately reproduce the magnetically doped II-IV Q-dots. In this work, we outline the minimal basis sets required to properly describe ZnO bonds in a nanocluster. It was demonstrated that the rock salt nanophase is incorrectly stabilized if a basis set does not contain sufficiently diffuse functions while the correct wurtzite phase is stabilized when diffuse functions are added. This tendency, similar to that in the ZnO dimer case, was shown to stem from the incorrect lack of Zn(4p) electron density in calculations when using the diffuse-free basis set.
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http://dx.doi.org/10.1002/jcc.26413DOI Listing
November 2020

Dissociation of Singly and Multiply Charged Nitromethane Cations: Femtosecond Laser Mass Spectrometry and Theoretical Modeling.

J Phys Chem A 2020 Sep 3;124(37):7427-7438. Epub 2020 Sep 3.

Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States.

Dissociation pathways of singly- and multiply charged gas-phase nitromethane cations were investigated with strong-field laser photoionization mass spectrometry and density functional theory computations. There are multiple isomers of the singly charged nitromethane radical cation, several of which can be accessed by rearrangement of the parent CH-NO structure with low energy barriers. While direct cleavage of the C-N bond from the parent nitromethane cation produces NO and CH, rearrangement prior to dissociation accounts for fragmentation products including NO, CHOH, and CHNO. Extensive Coulomb explosion in fragment ions observed at high laser intensity indicates that rapid dissociation of multiply charged nitromethane cations produces additional species such as CH, H, and NO.  On the basis of analysis of Coulomb explosion in the mass spectral signals and pathway calculations, sufficiently intense laser fields can remove four or more electrons from nitromethane.
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http://dx.doi.org/10.1021/acs.jpca.0c06545DOI Listing
September 2020

Homocoupling and Heterocoupling of Grignard Perfluorobenzene Reagents via Aryne Intermediates: A DFT Study.

J Phys Chem A 2019 Nov 4;123(45):9693-9700. Epub 2019 Nov 4.

Department of Physics , Florida A&M University , Tallahassee , Florida 32307 , United States.

Perfluorobenzenes are reactive species with the lowest magnesium metalation barriers among all hexahalobenzenes. This fact makes them good candidates for the study of heterocoupling reactions of the Grignard type. In this work, we investigated a number of pathways for both heterocoupling and homocoupling reactions and estimated the solvated energy barrier heights. According to the results of our density functional theory (DFT)-based computations, the heterocoupling reaction (CF)MgF + CF is a single-step process. We have also studied the (CF)MgF + (CF)MgF homocoupling reaction with an aryne intermediate. In this particular reaction, a carbon-carbon bond is formed between two nucleophilic carbon centers in a chemically predictable way. The final product, (CF)MgF, retains even stronger nucleophilic activity than that of the starting (CF)MgF reagent. A very surprising result of our calculations is that this homocoupling of two nucleophilic centers is spontaneous in THF solvent.
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http://dx.doi.org/10.1021/acs.jpca.9b05623DOI Listing
November 2019

NbB: a new member of half-sandwich type doped boron clusters with high stability.

Phys Chem Chem Phys 2019 Oct;21(39):21746-21752

Department of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, China.

A theoretical study of geometrical structures and electronic properties of niobium-doped boron clusters is performed using the CALYPSO approach for the global minimum search followed by density functional theory calculations. It is found that the global minima obtained for the neutral clusters correspond to the half-sandwich structures at n = 10-17 and the tubular-type structures at n = 18-20. The geometrical patterns in the anion series are more complex. The geometries undergo a transformation from the wheel-like structure of NbB10- to the half-sandwich ones beginning at n = 11 and finally to the drum-shaped structures at n ≥ 18. A fascinating NbB12- cluster is uncovered by our structural search, which shows robust stability and can be considered as a new member of the half-sandwich transition metal doped boron clusters. The chemical bond analysis indicates that the high stability is due to the strong interactions between the Nb atom and the B12 host as well as to the strong B-B covalent bonds. Our study will enrich the database of geometrical structures of transition metal doped boron clusters and will stimulate future synthesis of boron-based nanomaterials.
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http://dx.doi.org/10.1039/c9cp03496jDOI Listing
October 2019

Structural evolution and electronic properties of medium-sized boron clusters doped with scandium.

J Phys Condens Matter 2019 Dec 14;31(48):485302. Epub 2019 Aug 14.

Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, People's Republic of China.

Doping of boron-based materials with transition metal atoms allows one to tune or modify the properties and structure of the materials. In this work, an extensive search for the global minima on potential energy surfaces of ScB and ScB[Formula: see text] clusters has been performed using the CALYPSO method. The structural evolution of scandium doped boron clusters of this range is found to proceed in three steps; namely, the formation of half-sandwich type structures is followed by the formation of drum-like structures with the Sc atom located at the center and terminates with the cage-like structures. It is also found that highly symmetrical geometric structures are more common for the smaller size range of [Formula: see text]. The neutral ScB cluster is identified as magic on the basis of an analysis of relative stabilities in the ScB series. Our analysis of chemical bonding has shown that the stability of this cluster is mainly due to the formation of several delocalized [Formula: see text]-bonding molecular orbitals composed of Sc 3d and B 2s atomic orbitals. These bonds appear to be responsible for the enhanced stability of ScB with respect to other Sc-doped boron clusters.
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http://dx.doi.org/10.1088/1361-648X/ab3b2bDOI Listing
December 2019

Insights into the effects produced by doping of medium-sized boron clusters with ruthenium.

Phys Chem Chem Phys 2018 Dec;20(48):30376-30383

Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.

Modification of properties of boron nanoparticles by doping with transition metals presents a challenging problem because the number of isomers of both doped and un-doped nanoparticles rapidly increases with the nanoparticle size. Here, we perform a study of neutral and anionic Ru-doped boron clusters RuBn (n = 9-20) using the unbiased CALYPSO structural search method in combination with density functional theory calculations. Our results show that the neutral RuB9 cluster possesses a perfect planar wheel-like geometrical structure, whereas the RuBn clusters prefer structures of the half-sandwich type in the range of 10 ≤ n ≤ 14, drum-like type in the range of 15 ≤ n ≤ 18 and cage-like structures for larger n values. The geometrical structures of the lowest total energy states of the RuBn- anions are similar to those of the corresponding neutrals, except for RuB10-, RuB11-, RuB14-, RuB15- and RuB20-. The neutral RuB12 and RuB14 clusters are found to exhibit enhanced stability with respect to the rest of the RuBn clusters due to the delocalized bonding between the Ru atom and the boron host.
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http://dx.doi.org/10.1039/c8cp05725gDOI Listing
December 2018

Dissociation dynamics of 3- and 4-nitrotoluene radical cations: Coherently driven C-NO bond homolysis.

J Chem Phys 2018 Apr;148(13):134305

Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA.

Monosubstituted nitrotoluenes serve as important model compounds for nitroaromatic energetic molecules such as trinitrotoluene. This work investigates the ultrafast nuclear dynamics of 3- and 4-nitrotoluene radical cations using femtosecond pump-probe measurements and the results of density functional theory calculations. Strong-field adiabatic ionization of 3- and 4-nitrotoluene using 1500 nm, 18 fs pulses produces radical cations in the ground electronic state with distinct coherent vibrational excitations. In both nitrotoluene isomers, a one-photon excitation with the probe pulse results in NO loss to form CH, which exhibits out-of-phase oscillations in yield with the parent molecular ion. The oscillations in 4-nitrotoluene with a period of 470 fs are attributed to the torsional motion of the NO group based on theoretical results showing that the dominant relaxation pathway in 4-nitrotoluene radical cations involves the rotation of the NO group away from the planar geometry. The distinctly faster oscillation period of 216 fs in 3-nitrotoluene is attributed to an in-plane bending motion of the NO and CH moieties based on analysis of the normal modes. These results demonstrate that coherent nuclear motions determine the probability of C-NO homolysis in the nitrotoluene radical cations upon optical excitation within several hundred femtoseconds of the initial ionization event.
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http://dx.doi.org/10.1063/1.5024892DOI Listing
April 2018

Ultrafast coherent vibrational dynamics in dimethyl methylphosphonate radical cation.

Phys Chem Chem Phys 2018 Feb;20(7):4636-4640

Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA.

Femtosecond pump-probe measurements of the nerve agent simulant dimethyl methylphosphonate (DMMP) demonstrate the preparation of a robust coherent vibrational state in the corresponding radical cation. The oscillations in the transient ion yields have a period of 45 fs (750 cm), which is at least 3 times faster than any previously observed oscillations in polyatomic radical cations. Use of 1200-1600 nm, as opposed to 800 nm, wavelengths for ionization increases the oscillation amplitude by a factor of 5 and doubles the number of visible oscillation periods from 6 to 12, indicating that an adiabatic ionization mechanism significantly enhances preparation of the coherent state. The coherent motion is assigned to a bending mode in DMMP with frequency in the range of 742.2-754.7 cm based on the results of DFT calculations. The observation of coherent nuclear dynamics in the dissociation of DMMP suggests the potential utility of coherent control schemes for controlling the dissociation of DMMP and related molecules, which has important implications for developing detection and decontamination technologies for organophosphorus chemical warfare agents.
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http://dx.doi.org/10.1039/c7cp07261aDOI Listing
February 2018

Structure and Electronic Properties of Neutral and Negatively Charged RhB Clusters (n = 3-10): A Density Functional Theory Study.

J Phys Chem A 2017 Aug 18;121(34):6510-6516. Epub 2017 Aug 18.

Department of Physics, Florida A&M University , Tallahassee, Florida 32307, United States.

The geometrical structure and electronic properties of the neutral RhB and singly negatively charged RhB clusters are obtained in the range of 3 ≤ n ≤ 10 using the unbiased CALYPSO structure search method and density functional theory (DFT). A combination of the PBE0 functional and the def2-TZVP basis set is used for determining global minima on potential energy surfaces of the Rh-doped B clusters. The photoelectron spectra of the anions are simulated using the time-dependent density functional theory (TD-DFT) method. Good agreement between our simulated and experimentally obtained photoelectron spectra for RhB provides support to the validity of our theoretical method. The relative stabilities of the ground-state RhB and RhB clusters are estimated using the calculated binding energies, second-order total energy differences, and HOMO-LUMO gaps. It is found that RhB and RhB are the most stable species in the neutral and anionic series, respectively. The chemical bonding analysis reveals that the RhBcluster possesses two sets of delocalized σ and π bonds. In both cases, the Hückel 4N + 2 rule is fulfilled and this cluster possesses both σ and π aromaticities.
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http://dx.doi.org/10.1021/acs.jpca.7b06123DOI Listing
August 2017

Structure and properties of iron oxide clusters: From Fe6 to Fe6 O20 and from Fe7 to Fe7 O24.

J Comput Chem 2016 10 24;37(28):2527-36. Epub 2016 Aug 24.

College of Engineering & Science, Louisiana Tech University, Ruston, Louisiana, 71272.

Geometrical and electronic structures of the neutral and singly negatively charged Fe6 On and Fe7 Om clusters in the range of 1 ≤ n ≤ 20 and 1 ≤ m ≤ 24, respectively, are computed using density functional theory with the generalized gradient approximation. The largest clusters in the two series, Fe6 O20 and Fe7 O24 , can be described as Fe(FeO4 )5 and Fe(FeO4 )6 or alternatively as [FeO5 ](FeO3 )5 and [FeO6 ](FeO3 )6 , respectively. The Fe6 O20 and Fe7 O24 clusters possess adiabatic electron affinities (EAad ) of 5.64 eV and 5.80 eV and can be attributed to the class of hyperhalogens since FeO4 is an unique closed-shell superhalogen with the EAad of 3.9 eV. The spin character of the lowest total energy states in both series changes from ferromagnetic to ferrimagnetic or antiferromagnetic when the first FeOFe bridge is formed. Oxidation decreases substantially the polarizability per atom of the initial bare clusters; namely, from 5.98 Å(3) of Fe6 to 2.47 Å(3) of Fe6 O20 and from 5.67 Å(3) of Fe7 to 2.38 Å(3) of Fe7 O24 . The results of our computations pertaining to the binding energies of O, Fe, O2 , and FeO in the Fe7 Om series provide an explanation for the experimentally observed abundance of the iron oxide nanoparticles with stoichiometric compositions. © 2016 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/jcc.24478DOI Listing
October 2016

Structure and properties of the aluminum borates Al(BO2)n and Al(BO2)n(-), (n = 1-4).

J Comput Chem 2012 Feb 25;33(4):416-24. Epub 2011 Nov 25.

Department of Physics, Florida A&M University, Tallahassee, Florida 32307, USA.

The geometrical and electronic structures of Al(BO(2))(n) and Al(BO(2))(n)(-) (n = 1-4) clusters are computed at different levels of theory including density functional theory (DFT), hybrid DFT, double-hybrid DFT, and second-order perturbation theory. All aluminum borates are found to be quite stable toward the BO(2) and BO(2)(-) loss in the neutral and anion series, respectively. Al(BO(2))(4) belongs to the class of hyperhalogens composed of smaller superhalogens, and should possess a large adiabatic electron affinity (EA(ad)) larger than that of its superhalogen building block BO(2). Indeed, the aluminum tetraborate possesses the EA(ad) of 5.6 eV, which, however, is smaller than the EA(ad) of 7.8 eV of the AlF(4) supehalogen despite BO(2) is more electronegative than F. The EA(ad) decrease in Al(BO(2))(4) is due to the higher thermodynamic stability of Al(BO(2))(4) compared to that of AlF(4). Because of its high EA and thermodynamic stability, Al(BO(2))(4) should be capable of forming salts with electropositive counter ions. We optimized KAl(BO(2))(4) as corresponding to a unit cell of a hypothetical KAl(BO(2))(4) salt and found that specific energy and energy density of such a salt are competitive with those of trinitrotoluol (TNT).
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http://dx.doi.org/10.1002/jcc.21984DOI Listing
February 2012

Interactions of a Mn atom with halogen atoms and stability of its half-filled 3d-shell.

J Chem Phys 2011 Jun;134(23):234311

Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284, USA.

Using density functional theory with hybrid exchange-correlation potential, we have calculated the geometrical and electronic structure, relative stability, and electron affinities of MnX(n) compounds (n = 1-6) formed by a Mn atom and halogen atoms X = F, Cl, and Br. Our objective is to examine the extent to which the Mn-X interactions are similar and to elucidate if/how the half-filled 3d-shell of a Mn atom participates in chemical bonding as the number of halogen atoms increases. While the highest oxidation number of the Mn atom in fluorides is considered to be +4, the maximum number of halogen atoms that can be chemically attached in the MnX(n)(-) anions is 6 for X = F, 5 for X = Cl, and 4 for X = Br. The MnCl(n) and MnBr(n) neutrals are superhalogens for n ≥ 3, while the superhalogen behavior of MnF(n) begins with n = 4. These results are explained to be due to the way different halogen atoms interact with the 3d electrons of Mn atom.
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http://dx.doi.org/10.1063/1.3601753DOI Listing
June 2011

A systematic study of neutral and charged 3d-metal trioxides and tetraoxides.

J Chem Phys 2011 Apr;134(14):144305

Department of Physics, Virginia Commonwealth University, 701 West Grace Street, Richmond, Virginia 23284-2000, USA.

Using density functional theory with generalized gradient approximation, we have performed a systematic study of the structure and properties of neutral and charged trioxides (MO(3)) and tetraoxides (MO(4)) of the 3d-metal atoms. The results of our calculations revealed a number of interesting features when moving along the 3d-metal series. (1) Geometrical configurations of the lowest total energy states of neutral and charged trioxides and tetraoxides are composed of oxo and∕or peroxo groups, except for CuO(3)(-) and ZnO(3)(-) which possess a superoxo group, CuO(4)(+) and ZnO(4)(+) which possess two superoxo groups, and CuO(3)(+), ZnO(3)(+), and ZnO(4)(-) which possess an ozonide group. While peroxo groups are found in the early and late transition metals, all oxygen atoms bind chemically to the metal atom in the middle of the series. (2) Attachment or detachment of an electron to∕from an oxide often leads to a change in the geometry. In some cases, two dissociatively attached oxygen atoms combine and form a peroxo group or a peroxo group transforms into a superoxo group and vice versa. (3) The adiabatic electron affinity of as many as two trioxides (VO(3) and CoO(3)) and four tetraoxides (TiO(4), CrO(4), MnO(4), and FeO(4)) are larger than the electron affinity of halogen atoms. All these oxides are hence superhalogens although only VO(3) and MnO(4) satisfy the general superhalogen formula.
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http://dx.doi.org/10.1063/1.3570578DOI Listing
April 2011

Negative ions of transition metal-halogen clusters.

J Chem Phys 2010 Oct;133(14):144301

Department of Physics, Virginia Commonwealth University, 701 W Grace Street, Richmond, Virginia 23284-2000, USA.

A systematic density functional theory based study of the structure and spectroscopic properties of neutral and negatively charged MX(n) clusters formed by a transition metal atom M (M=Sc,Ti,V) and up to seven halogen atoms X (X=F,Cl,Br) has revealed a number of interesting features: (1) Halogen atoms are bound chemically to Sc, Ti, and V for n≤n(max), where the maximal valence n(max) equals to 3, 4, and 5 for Sc, Ti, and V, respectively. For n>n(max), two halogen atoms became dimerized in the neutral species, while dimerization begins at n=5, 6, and 7 for negatively charged clusters containing Sc, Ti, and V. (2) Magnetic moments of the transition metal atoms depend strongly on the number of halogen atoms in a cluster and the cluster charge. (3) The number of halogen atoms that can be attached to a metal atom exceeds the maximal formal valence of the metal atom. (4) The electron affinities of the neutral clusters abruptly rise at n=n(max), reaching values as high as 7 eV. The corresponding anions could be used in the synthesis of new salts, once appropriate counterions are identified.
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http://dx.doi.org/10.1063/1.3489117DOI Listing
October 2010