Lowest Isomers Research Articles

Unimolecular isomerizations of C6H6•+ radical cations: a computational study.

Eighteen concerted isomerization reactions of various C6H6•+ radical cation (RC) species are studied and found to proceed via well-defined transition states, whose relative positions along the reaction pathway generally agree with Hammond's postulate. From the barrier heights, the rate coefficients of these reactions are estimated by using transition state theory, and the activation energies are computed. Through combination among themselves, these 18 isomerizations yielded 15 multi-step conversion routes of various C6H6•+ species to the lowest energy benzene radical cation isomer 1, which routes are compared. Use is made of DFT with the B3LYP and M06-2X functionals, along with the CBS-QB3 approach to arrive at better energies. From the barrier heights for each of the concerted reactions, canonical transition state theory was applied to evaluate rate coefficients k over the temperature range 200-500K. The Arrhenius activation energies were computed using the plot of ln k vs. 1/T.

Comments on “Planar Tetracoordinate Hydrogen: Pushing the Limit of Multicentre Bonding”

AbstractIn a recent communication (Angew. Chem. Int. Ed. 2024, 63, e202317312), Kalita et al. studied In4H+ system within the frame of single‐reference approximation (SRA) and found that the global energy minimum (1 a) adopted the singlet state and a planar tetracoordinate hydrogen (ptH), while the second lowest isomer (1 b) located 3.0 kcal/mol above 1 a and adopted the triplet state as well as non‐planar structure with a quasi‐ptH. They assessed the reliability of SRA by checking the T1‐diagnostic values of coupled cluster calculations. However, according to our multi‐configurational second‐order perturbation theory calculations at the CASPT2(12,13)/aug‐cc‐pVQZ (aug‐cc‐pVQZ‐PP for In) level, both 1 a and 1 b exhibit obvious multi‐referential characters, as reflected by their largest reference coefficients of 0.928 (86.1 %) and 0.938 (88.0 %), respectively. Moreover, 1 b is 5.05 kcal/mol lower than 1 a at this level, that is, what can be observed in In4H+ system is the quasi‐ptH.

Emin: A First-Principles Thermochemical Descriptor for Predicting Molecular Synthesizability.

Predicting the synthesizability of a new molecule remains an unsolved challenge that chemists have long tackled with heuristic approaches. Here, we report a new method for predicting synthesizability using a simple yet accurate thermochemical descriptor. We introduce Emin, the energy difference between a molecule and its lowest energy constitutional isomer, as a synthesizability predictor that is accurate, physically meaningful, and first-principles based. We apply Emin to 134,000 molecules in the QM9 data set and find that Emin is accurate when used alone and reduces incorrect predictions of "synthesizable" by up to 52% when used to augment commonly used prediction methods. Our work illustrates how first-principles thermochemistry and heuristic approximations for molecular stability are complementary, opening a new direction for synthesizability prediction methods.

Spectroscopy and photochemistry of ClSSO.

Sulfur-chlorine cycles play a role in the atmosphere of Venus. It is thought that many sulfur-chlorine bearing molecules could be present in Venus's atmosphere and play an important role in its chemical processes. The goal of this work is to provide new insight into the electronic structure and spectroscopy of the [Cl, S, S, O] molecular system. Eight isomers could be formed, but only three were found to be thermodynamically stable relative to the first dissociation limit. We spectroscopically characterized the two lowest energy stable isomers, C1-ClSSO and trans-ClSSO, using the accurate CCSD(T)-F12/aug-cc-pVTZ method. The dipole moments of the two lowest energy stable isomers are predicted to be 1.90 and 1.60 debye, respectively. The C1-ClSSO isomer is suitable for laser induced fluorescence detection since the lowest excited electronic states absorb in the visible, ∼610 nm, and near UV region, 330 nm. We mapped the evolution of the low-lying excited electronic states along the ClS, SS, and SO bond lengths to find that the production of ClS, SO, or S2O is plausible, whereas the production of ClS2 is not allowed.

Prediction of the structures and heats of formation of MO2, MO3, and M2O5 for M = V, Nb, Ta, Pa.

Structures for the mono-, di-, and tri-bridge isomers of M2O5 as well as those for the MO2 and MO3 fragments for M = V, Nb, Ta, and Pa were optimized at the density functional theory (DFT) level. Single point CCSD(T) calculations extrapolated to the complete basis set (CBS) limit at the DFT geometries were used to predict the energetics. The lowest energy dimer isomer was the di-bridge for M = V and Nb and the tri-bridge for M = Ta and Pa. The di-bridge isomers were predicted to be composed of MO2+ and MO3- fragments, whereas the mono- and tri-bridge are two MO2+ fragments linked by an O2-. The heats of formation of M2O5 dimers, as well as MO2 and MO3 neutral and ionic species were predicted using the Feller-Peterson-Dixon (FPD) approach. The heats of formation of the MF5 species were calculated to provide additional benchmarks. Dimerization energies to form the M2O5 dimers are predicted to become more negative going down group 5 and range from -29 to -45 kcal mol-1. The ionization energies (IEs) for VO2 and TaO2 are essentially the same at 8.75 eV whereas the IEs for NbO2 and PaO2 are 8.10 and 6.25 eV, respectively. The predicted adiabatic electron affinities (AEAs) range from 3.75 eV to 4.45 eV for the MO3 species and vertical detachment energies from 4.21 to 4.59 eV for MO3-. The calculated MO bond dissociation energies increase from 143 kcal mol-1 for M = V to ∼170 kcal mol-1 for M = Nb and Ta to ∼200 kcal mol-1 for M = Pa. The M-O bond dissociation energies are all similar ranging from 97 to 107 kcal mol-1. Natural bond analysis provided insights into the types of chemical bonds in terms of their ionic character. Pa2O5 is predicted to behave like an actinyl species dominated by the interactions of approximately linear PaO2+ groups.

Ground state spectroscopy and photochemistry of HAlOH.

Ab initio calculations were carried out in order to study the electronic structure and spectroscopy of cis-HAlOH, trans-HAlOH, H2AlO, and AlOH2. The cis structure is more stable than the trans, and both are thermodynamically stable relative to the AlOH + H dissociation limit. A set of spectroscopic constants were generated for the lowest stable isomers to help with their detection in the laboratory and in the interstellar medium. The first excited state absorbs strongly in the visible region (λ = 460nm), with a predicted transition dipole moment of 2.07D. The electronic structures of the first excited state were calculated, including the lifetime, adiabatic excitation energy, rotational constants, and frequencies. We have shown that both isomers may be suitable for laser-induced fluorescence detection. Finally, photodissociation of the cis- and trans-HAlOH isomers is a plausible mechanism for the production of AlOH and H.

Energy Landscape and Structural and Spectroscopic Characterization of Diazirine and Its Cyclic Isomers

Identifying new nitrogenated hydrocarbon molecules in the interstellar medium (ISM) is challenging because of the lack of comprehensive spectroscopic data from experiments. In this computational work, we focus on investigating the structures, relative energies, spectroscopic constants, and energy landscape of the cyclic isomers of diazirine (c-CH2N2) using ab initio quantum chemical methods. Density functional theory (DFT) methods and coupled cluster theory with singles and doubles including perturbative triples [CCSD(T)] and CCSD(T) with the explicitly correlated F12b correction [CCSD(T)-F12b] were employed for this purpose along with large correlation consistent cc-pVTZ, cc-pVQZ, and cc-pV5Z basis sets. Harmonic vibrational frequencies, infrared vibrational intensities, rotational constants, and dipole moments are reported. Anharmonic vibrational fundamentals along with centrifugal distortion constants, and vibration-rotation interaction constants are also reported for all the cyclic isomers. The energies computed with the CCSD(T) and CCSD(T)-F12b methods were extrapolated to the one-particle complete basis set (CBS) limit following a three-point formula. At the CCSD(T)-F12b/CBS level of theory, the 3,3H-diazirine (c-CH2N2) is the lowest energy cyclic isomer followed by 1,3H-diazirine, (E)-1,2H-diazirine, and (Z)-1,2H-diazirine, which are 20.1, 47.8, and 51.3 kcal mol-1 above the 3,3H-diazirine, respectively. Accurate structures and spectroscopic constants that are reported here could be useful for future identification of these cyclic nitrogenated organic molecules in the interstellar medium or circumstellar disks.

Low-lying isomers of (TiO2)n (n=2−8) clusters

Although there are diverse bond features of Ti and O atoms, so far only several isomers have been reported for each (TiO2)n cluster. Instead of the widely used global optimization, in this work, we search for the low-lying isomers of (TiO2)n (n=2−8) clusters with up to 10000 random sampling initial structures. These structures were optimized by the PM6 method, followed by density functional theory calculations. With this strategy, we have located many more low-lying isomers than those reported previously. The number of isomers increases dramatically with the size of the cluster, and about 50 isomers were found for (TiO2)7 and (TiO2)8 with the energy within 30 kcal/mol. Furthermore, new lowest isomers have been located for (TiO2)5 and (TiO2)8, and isomers with three terminal oxygen atoms, five coordinated oxygen atoms as well as six coordinated titanium atoms have been located. Our work highlights the diverse structural features and a large number of isomers of small TiO2 clusters.

DFT characterisation of a PdII → IIII adduct, and a PdII complex formed after oxidative alkenylation of PdII by [Ph(alkenyl)IIII]+, in Pd-mediated synthesis of benzofurans involving PdIV, annulation and chain-walking.

The synthesis of benzofurans by the reaction of the palladium(II) complex Pd{1-C6H4-2-OCH(CO2Et)-C,C}(bipy) (bipy = 2,2'-bipyridine) with hypervalent iodine(III) reagents [Ph(CHCHR)I]+ has been examined by Density Functional Theory. Results highlight the role of oxidative alkenylation to form PdIV intermediates and the role of initial adduct formation in this process, an annulation process facilitated by PdII, and the role of 'chain-walking' at PdII centres to allow formation of the lowest energy product. Computation (R = Me) allows assignment of an initially formed adduct with a 'PdII → IIII' interaction at -50 °C, and, after oxidative alkenylation of PdII and reductive elimination from a PdIV centre via Ar⋯Alkenyl coupling, formation of a second intermediate with a structure consistent with NMR detection (R = n-hexyl) at -30 °C is obtained. This PdII complex, containing a coordinated alkene group in Pd{1-(RHCγCβ)C6H4-2-OCαH(CO2Et)-η2-CαCβ,C}(bipy), undergoes a 5-exo-trig annulation by forming a Cα-Cβ bond to give a complex with a bicyclic carbon skeleton suitable for subsequent formation of benzofurans. A series of facile rearrangements including chain-walking results in formation of a lowest energy complex of three feasible hydrido(alkene)palladium(II) species, leading to decomposition and release of the observed benzofuran isomer isolated under synthesis conditions. The computational study allows reinterpretation of the NMR data reported previously, in particular the determination of barriers in the reaction pathway allowing assignment of structure for key intermediates.

RETRACTED: An Ab initio study on effects of doping into Pt13 cluster with Ag, Ir and Pd

It is well known that doping is an efficient tool to modify the properties of clusters. Here, the results of the ab initio calculations on the effects of substitutional doping of Ag, Ir, and Pd atoms on the atomic and electronic structure of Pt 13 cluster are reported. The plane wave method and spin-polarized Exchange-correlation function have been used to study the various low-lying isomers of Pt 13 and to identify the lowest energy structures of the doped clusters. Moreover, this work involves studying about different doping sites and different magnetization values, exclusively for each isomer. Doing this way, the stability of the atom cluster has been analyzed and that is based on the low energy of the isomers calculated by the total energy with spin-polarized, lowest values of HOMO-LUMO gap, and higher values of the binding energy of each atom in the Pt 13 cluster structure. The resulting lowest energy structures show that in the case of Pt 12 Ir, the lowest energy isomer changes compared to the Pt 12 Ag and Pt 12 Pd clusters. Further, Bader charge analysis has been performed for calculating the charge transfer between the dopant and the host cluster which shows a charge transfer from −1.37 to +0.74 e. The study also reports about the changes that had happened in the electronic structure and magnetic properties of the Pt 13 cluster due to the dopant. This work helps to understand about the energy changes that occur during magnetic moment variations on the atomic cluster, DoS, and about analyzing this energy changes while spinning the atoms. • Effects of substitutional doping of Ag, Ir and Pd atoms with atomic structure of Pt13 cluster. • Study on several low-lying isomers of Pt13 cluster to identify the lowest energy structures of the doped clusters using Exchange-correlation functional methods. • Changes in energy by varying the magnetic moments on the cluster in order to obtain the lowest energy spin isomer. • Usage of Double Triangle, a distorted CDT, FCC-1, Double pyramid, Icosahedron and Decahedron. Total energy calculation on Vertex, Capping and Center doping sites on each isomer.

Electronic Structure and Electron Delocalization in Bare and Dressed Boron Pentamer Clusters.

The electronic structures of the lowest energy spin-states of the cationic, neutral and anionic bare boron pentamer clusters have been investigated by means of high level multiconfigurational type calculations, in view of the large static and dynamical electron correlation effects for these species. We found that resembles a singlet spin-state perfect pentagon, which bears no intra-annular chemical bonding interactions, as shown by our analysis of the electron delocalization carried out in terms of the normalized Giambiagi ring-current index, and the total and adjacent atom-pair delocalization indices. However, its lowest-energy triplet and quintet spin-state isomers have C2v symmetry, with large intra-annular chemical bonding interactions. This geometrical feature extends to both the neutral and the anionic species. Namely, the lowest-energy isomers of boron pentamer neutral and anionic clusters have peripheral and intra-annular sizable bonding interactions reflected in the delocalization of both π- and σ-type valence natural orbitals over the whole molecular plane, which impart large structural stability. In accordance to our calculations, the lowest energy triplet spin-state isomer of the anionic boron pentamer cluster has C2 symmetry, and consequently, it should show optical activity. Finally, we have studied the change of the geometrical structure of the boron pentamer clusters from planar to compact three-dimensional structures caused by the bonding of ligands to the boron atoms. Our explicit all-electron calculations have been rationalized in terms of the shell-closure of the delocalized valence orbitals of the clusters as predicted by the jellium model extended to nonspherical confinement potentials, circumscribing the role of the ligand to modulate the total number of valence electrons assigned to the core cluster.

Theoretical Study of Small-Sized Carbon Clusters and the Formation of Fullerene Cages

Systematical DFT study on small-sized carbon chains, rings, bowls and cages are performed. For carbon chains, the results show that the end bond will shorten compared with its nearest adjacent bond; the bond lengths are not alternated but symmetrically distributed based on the central atom (odd-number chains) and the middle point (even-number chains). Odd-number carbon chains are singlet and even-number chains are triplet. The diffidence in lengths of adjacent two bonds is slightly and much smaller than the length difference between triple and single bond in C2H2 and C2H6. All theoretical evidences here show that linear chains of carbon are polyene not polyalkyne. For carbon rings, their highest symmetrical (Dnh) isomers of Cn are not lowest energy ring isomers except for C25-Ring. For carbon cages, the interesting findings include (1) a new non-classical isomer of C24 is found to be more favored than the classical one which was reported to be most favored; (b) a new non-classical isomer of C26 is found to be more favored than the classical one which was reported to be the 2nd favored; (c) Small cages welcome strained square(s); and (d) The favored cages of them are structurally related to direct C2 insertion/extrusion. Comprehensive comparison show that carbon chains are more favored than rings and cages when n≤9,however, rings are more favored than chains when 10≤n≤20; Bowls/sheets are more favored than cages energetically for clusters of Cn with 18≤n≤24; The cages are increasing favorable and become dominant species when n≥26. These results clearly suggest the structural evolution from chains to rings or bowls and cages in turn.

Superhalogens in fluoride diruthenium Ru2Fn (n = 1–10): density functional theory

The structures of the lowest and a few higher isomers for Ru2 Fn (n = 1–10) clusters are obtained based on functional B3P86 with 6–311 + g(d) for fluorine and LANL2DZ for ruthenium. The results show that Ru2 Fn (n = 5–10) clusters investigated represent superhalongens characterized by the vertical electron affinity energies (VEA) significantly exceeding 3.8 eV. The VEA values estimated for the Ru2 F5 , Ru2 F6 , Ru2 F7 , Ru2 F8 , Ru2 F9 , and Ru2 F10 systems are predicted to be 3.8 eV, 4.5 eV, 5.7 eV, 6.0 eV, 6.1 eV, and 6.8 eV. The stabilities of the lowest isomers for Ru2 Fn (n = 5–10) and the chemical bonds between the two metal atoms are analyzed. The energy gap, vibration frequency, vertical electron affinity energy, vertical ionization energy and frontier molecular orbitals of these Ru2 Fn clusters are also calculated. The spin polarization of Ru2 Fn clusters originate mainly from Ru 4d orbitals, which determines the magnetism of the systems.

First-principles study of AuSn (2 ≤ n ≤ 7) clusters: structural, electronic, magnetic, spectral properties, and adsorption properties with O2 and H2O

Based on the density functional theory (DFT) method, the geometrical structures, relative stability, electronic, and spectral properties of AuSn (2 ≤ n ≤ 7) clusters are systematically studied, whose sizes are largely in the range of 0.3–0.5 nm. AuS4 and AuS3 show the highest and lowest energy gaps and hence the highest chemical stability and chemical activity, respectively. The total magnetic moment is 3.0 and 1 (or 0) μB for AuS4 and other clusters, respectively, which largely (about 99.9%) arise from the local magnetic moment of S atoms. The average polarization tensor for single atom ( ) generally increases with increasing the number of S atoms, with the maximum 91.72 a.u. for AuS7, corresponding to the most significant delocalization effect. AuS4 cluster exhibits the highest polarizability anisotropic invariant Δα (≈ 350.56 a.u.) and the lowest total dipole moment (≈ 0.06 D) among all systems, corresponding to the strongest anisotropic response to external electric field and the weakest polarization, respectively. The IR, Raman, UV-Vis, and PES spectra are simulated for AuSn (2 ≤ n ≤ 7) clusters with the structures of the lowest isomers. The O–O and O–H bond lengths, adsorption energies, vibration frequencies, and density of states are also calculated for AuS4 and AuS3 adsorbing one O2 and H2O molecules, respectively. The adsorption capacity of AuS3 for both gas molecules is higher than AuS4, and AuSn (n = 3, 4) clusters are more favor to adsorb O2 than H2O.

Exploring Cage‐warped Rotation Isomers of C20 Fullerene: MP2 and Density Functional Calculations

Using the density functional methods B3LYP, M06‐2X, PBE1PBE, B3LYP D3, M06‐2X D3, and PBE1PBE D3, and the ab initio MP2 calculations, the optimized atomic structures and energies of C20 cage rotation isomers without a constraint were obtained. The reaction path between the two rotational isomers was then studied, in which there are three local stable atomic structures. One is the most stable fullerene structure with the D2h point group staggered between the upper and bottom pentagons (ST) and the other is the second lowest energy rotational isomer with the Cs point group eclipsed between the upper and bottom pentagons (EC) with a torn fullerene structure (M1) between ST and EC. The first transition structure T1 between the ST and the M1, and the second transition structure T2 between the M1 and the EC were then obtained along the reaction coordinate between these three structures. Vibration analysis of all optimized structures including the transition structures without a constraint was carried out. For each of the rotational isomers obtained by our calculations, thermodynamic stability was explained with the relative energy difference, and then the kinetic stability was analyzed as the HOMO–LUMO energy difference.

Neutral Rhenadicarbaboranes with Re(CO)2(NO) Vertices: A Theoretical Study of Building Blocks for Rhenacarborane-Based Drug Delivery Agents.

The rhenadicarbaborane carbonyl nitrosyls (C2Bn−3Hn−1)Re(CO)2(NO), (n = 8 to 12), of interest in drug delivery agents based on the experimentally known C2B9H11Re(CO)2(NO) and related species, have been investigated by density functional theory. The lowest energy structures of these rhenadicarbaboranes are all found to have central ReC2Bn−3 most spherical closo deltahedra in accord with their 2n + 2 Wadean skeletal electrons. Carbon atoms are found to be located preferentially at degree 4 vertices in such structures. Furthermore, rhenium atoms are preferentially located at a highest degree vertex, typically a vertex of degree 5. Only for the 9-vertex C2B6H8Re(CO)2(NO) system are alternative isocloso deltahedral isomers found within ~8 kcal/mol of the lowest energy closo isomer. Such 9-vertex isocloso structures provide a degree 6 vertex for the rhenium atom flanked by degree 4 vertices for each carbon atom.

Global Optimization of Li and Na Clusters: Application of a Modified Embedded Atom Method

An analytic modified embedded atom method (MEAM), developed for bulk alkali metals, is used to identify up to six different, energetically lowest isomers of $$\hbox {Li}_N$$ and $$\hbox {Na}_N$$ clusters (N = 2 − 150) within an unbiased global structure-optimization procedure. Randomly generated clusters are locally optimized using the quasi-Newton method and the resulting six most stable isomers are used afterwards in the Aufbau–Abbau algorithm. Due to its analytical formulae and its semiempirical nature, the MEAM emerges as a fast and efficient method that is particularly suitable for an unbiased global optimization. Structural and energetic analyses show that the MEAM provides compact clusters that are in good agreement with the results of other semiempirical calculations. Occasionally, the MEAM produces structures that are normally not found with such model potentials but in more accurate DFT or ab initio studies. Moreover, clusters of pronounced stability (magic sizes) are identified, growth patterns are studied, and trends can be recognized in which the atomic arrangement within the clusters of the considered size range corresponds more to the fcc than to the bcc packing. Additionally, for most cluster sizes the structures of the lowest-energy isomers of $$\hbox {Li}_N$$ and $$\hbox {Na}_N$$ clusters are very similar.

ESCAPE: A novel approach for a fast estimation of dynamic correlation energies: Application to large organic molecules.

Advanced wave function-based quantum chemical ab initio methods, such as CCSD(T), are able to calculate the energies of small- to medium-sized molecules with chemical accuracy. Unfortunately, these methods scale quite unfavorably with the size of the system and are getting too time consuming-and too expensive-for larger molecules. In order to be able to treat larger organic molecules, we propose a novel scheme for a quick and reliable estimate of molecular correlation energies, which we call ESCAPE (EStimation of CorrelAtion energies by Pair Energies). It is based on the pair correlation energies for localized molecular orbitals that have been generated by CCSD[T] and fitted to suitable functional forms. All fit parameters are stored in a large parameter file. Aiming at chemical accuracy (±1 kcal/mol), we have first limited our approach to aliphatic hydrocarbons. The total molecular CCSD[T] correlation energies of a training set of 41 aliphatic hydrocarbons could be reproduced with a mean absolute error (MAE) of 0.56 kcal/mol or 0.11%. A similar accuracy could be obtained for a test set of 11 additional hydrocarbons with up to eight carbon atoms (MAE of 0.65 kcal/mol or 0.09%). In a more critical test, we checked the small energy differences for a set of 13 isomerization reactions. The comparison with experimental data showed that we could reach chemical accuracy as well. Our estimate (MAE of 0.55 kcal/mol) is slightly inferior to the CCSD[T] result (MAE of 0.17 kcal/mol), but superior to SCF, DFT/B3LYP, and DFT/B3LYP + D3. Moreover, in all cases, we obtained the correct sign, that is, the correct equilibrium structure. A similar accuracy could be reached in an application to the three lowest isomers of the C60 molecule. Using the example of a set of eight alcohols, we were able to proof the method's ability for molecules including heteroatoms. Three fast steps are necessary for the application to any aliphatic hydrocarbon or alcohol: (1) An SCF calculation at the selected molecular geometry; it can be fast since a medium size basis set is generally sufficient. (2) The localization of the occupied molecular orbitals and determination of their properties (center of charge and spatial extent). (3) Estimate of the correlation energy using the existing parameter file. © 2019 Wiley Periodicals, Inc.

Quantum effects on the stability of the He5 I2 van der Waals conformers.

We present 15-dimensional quantum multiconfiguration time-dependent Hartree calculations of the vibrational levels of the He5 I2 van der Waals (vdW) complex employing an ab initio-based potential energy surface (PES). The energies and spatial features of such bound structures are analyzed, providing predictions on the structures and relative stabilities of its three lowest isomers. We found that the most stable isomer corresponds to all five He atoms encircling the I2 molecule, indicating that in this case the anharmonic quantum effects do not stabilize the isomers involving a He atom in a linear configuration as reported previously for the smaller HeN I2 systems. Such finding provides information on the overall structuring of the finite-size-solvent systems, highlighting the intriguing interplay between weak intermolecular interactions and quantum effects. © 2019 Wiley Periodicals, Inc.

Theoretical studies of structural, electronic, and magnetic properties for small V2Fn0,− (2 ≤ n ≤ 7) clusters using first-principles calculations

The structural, electronic, and magnetic properties of V2Fn0,− (2 ≤ n ≤ 7) clusters are investigated by using density functional theory (DFT) calculations. The spin multiplicities of the lowest isomers of the optimized V2Fn0,− (2 ≤ n ≤ 7) clusters are generally high, and V2F6 exhibits the highest stability. The largest electron affinity (≈ 4.976 eV) of V2F7 among the systems may reflect superhalogen nature of this cluster. The polarizability analysis reveals that V2F2− or V2F5− cluster has the largest or smallest polarizability anisotropy invariant, corresponding to the strongest or weakest anisotropic response to the external field, respectively. The total magnetic moments of mixed V2Fn0,− clusters are in the range of 3–7 μB, mainly arising from the local magnetic moments of V atoms with unfilled 3d shell. The atoms at the symmetrical positions of the clusters have the same magnetic moments. As for the calculated IR and Raman spectra, the larger number n of F atoms of the clusters is associated with the more vibration peaks, with the highest peaks largely attributable to the stretching vibrations of F atoms.