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Photothermal therapy (PTT) has a great prospect in further improving tumor therapeutic outcomes, whereas its efficiency is restrained by low light penetration, excessive heat damage to normal tissues, up‐regulated heat shock proteins (HSPs), and limited effect of single treatment. Herein, an enzyme‐engineered coppery nanozyme based on dendritic mesoporous coppery carbon nanosphere as the cornerstone to load with glucose oxidase (GOx) followed by modification with hyaluronic acid is constructed. Density functional theory calculations indicate that the obtained coppery nanozyme exhibits peroxidase and glutathione oxidase mimicking activities to improve hydroxyl radicals (•OH) production. Furthermore, both the generation of •OH production and GOx‐induced energy supply blockade can reduce HSPs expression to enhance the mild PTT (η = 34.9 %) of coppery nanozyme upon the irradiation of 1064 nm laser, and in turn, accelerate the catalytic processes of coppery nanozyme for more generation of •OH. Last but not least, the introduction of copper can induce lipoylated protein dihydrolipoamide S‐acetyltransferase aggregation to cause cellular cuproptosis. Due to the synergy of multiple therapies, the tumor inhibition rate can reach 93.4%. Overall, this work provides an effective strategy for potential tumor treatment on the basis of synergistic therapies. [ABSTRACT FROM AUTHOR]

Abstract: As promising TBC (thermal barrier coating) candidates, perovskite oxides own designable properties for their various options of cations and structural diversity, but limited comprehensions of structure‐property relationship delay their engineering applications. In this work, mechanical/thermal properties of ABO3 (A=Sr, Ba; B=Ti, Zr, Hf) perovskites and their anisotropic nature are predicted employing density functional theory. Their theoretical minimum thermal conductivities range from 1.09 to 1.74 W·m−1·K−1, being lower than Y2O3 partially stabilized ZrO2. Reduced thermal conductivities up to 16% along particular directions are reached after considering thermal conductivity anisotropy. All compounds own high hardness while SrZrO3, SrHfO3, and BaHfO3 possess well damage tolerance. We found that small electronegativity discrepancy leads to big anisotropy of chemical bond, Young's/shear moduli and thermal conductivities, together with good damage tolerance. These results suggest that the next generation TBCs with extra low thermal conductivity should be achieved through combining material design and orientation‐growth tailoring. [ABSTRACT FROM AUTHOR]

In this paper the effect of thickness on angular‐dependent magnetoresistance (MR) of La2/3Sr1/3MnO3 (LSMO) thin films grown on SrTiO3 is systematically investigated. In films thinner than 8 nm, we observe an anomalous weak peak in the MR curves when the magnetic field is parallel to the film surface. In films thicker than 10 nm, however, the weak peak disappears and a novel MR valley appears when the magnetic field is perpendicular to the film surface. The weak peak is thought to be induced by the formation of two‐dimensional electron gas (2DEG) at the interface, which is confirmed by density functional theory calculations. The disappearance of the peak and appearance of the valley in the films thicker than 10 nm is associated with the formation of misfit dislocations near the interface between film and substrate, which are clearly visible in high‐resolution transmission electron microscopy images. Our work could shed significant light on the influence of film thickness on 2DEG formation. [ABSTRACT FROM AUTHOR]

Low-energy recoil events in Ti3SiC2 are studied using ab initio molecular dynamics simulations. We find that the threshold displacement energies are orientation dependent because of anisotropic structural and/or bonding characteristic. For Ti and Si in the Ti-Si layer with weak bonds that have mixed covalent, ionic, and metallic characteristic, the threshold displacement energies for recoils perpendicular to the basal planes are larger than those parallel to the basal planes, which is an obvious layered-structure-related behavior. The calculated minimum threshold displacement energies are 7 eV for the C recoil along the [ABSTRACT FROM AUTHOR]

In this article, we describe a C/C++ program called SurfKin (Surface Kinetics) to construct microkinetic mechanisms for modeling gas-surface reactions. Thermodynamic properties of reaction species are estimated based on density functional theory calculations and statistical mechanics. Rate constants for elementary steps (including adsorption, desorption, and chemical reactions on surfaces) are calculated using the classical collision theory and transition state theory. Methane decomposition and water-gas shift reaction on Ni(111) surface were chosen as test cases to validate the code implementations. The good agreement with literature data suggests this is a powerful tool to facilitate the analysis of complex reactions on surfaces, and thus it helps to effectively construct detailed microkinetic mechanisms for such surface reactions. SurfKin also opens a possibility for designing nanoscale model catalysts. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction reaction (CO2RR) offers a sustainable strategy for producing fuels and chemicals. However, it suffers from sluggish CO2 activation and slow water dissociation. In this work, we construct a (P−O)δ− modified In catalyst that exhibits high activity and selectivity in electrochemical CO2 reduction to formate. A combination of in situ characterizations and kinetic analyses indicate that (P−O)δ− has a strong interaction with K+(H2O)n, which effectively accelerates water dissociation to provide protons. In situ attenuated total reflectance surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) measurements together with density functional theory (DFT) calculations disclose that (P−O)δ− modification leads to a higher valence state of In active site, thus promoting CO2 activation and HCOO* formation, while inhibiting competitive hydrogen evolution reaction (HER). As a result, the (P−O)δ− modified oxide‐derived In catalyst exhibits excellent formate selectivity across a broad potential window with a formate Faradaic efficiency as high as 92.1 % at a partial current density of ~200 mA cm−2 and a cathodic potential of −1.2 V vs. RHE in an alkaline electrolyte. [ABSTRACT FROM AUTHOR]

Rare earth silicates are promising environmental/thermal barrier coating (E/TBC) materials facing severe CMAS (CaO‐MgO‐Al2O3‐SiO2) corrosion. Previous studies mainly focused on the intrinsic properties of precorrosion coatings, but there were few studies on their CMAS corrosion products that play a crucial role in the performance of coatings in postservice stage. In this work, the mechanical and thermal properties of nine corrosion products between lutetium silicates and CMAS are studied using first‐principles calculations. Their differences of elastic stiffness are attributed to the different crystal structures and bonding strength. The T:O ratio is identified as a factor of the crystal structure for silicate products, and it has a good correlation with their elastic stiffness. Moreover, the divergences of thermal conductivity are dominated by three essential factors, that is, atomic vibration intensity, lattice vibrational anharmonicity, and complexity of crystal structure. Compared with rare earth silicates, six products, that is, the α‐CaSiO3, β‐CaSiO3, Ca2MgSi2O7, Ca2Al2SiO7, CaAl2Si2O8, and Ca2Lu8(SiO4)6O2, showing good damage tolerance and low thermal conductivities, are predicted to be advantageous to E/TBCs. These discoveries reveal the mechanical/thermal properties of corrosion products between lutetium silicates and CMAS and are expected to support the future researches on the performance of E/TBC in the postservice stage. [ABSTRACT FROM AUTHOR]

Domino reaction of benzo[d]thiazole‐2‐methylamine (S1) has been developed in the presence of MnCl2 ⋅ 4H2O, leading to tetrasubstituted pyrrole coordinated dinuclear Mn(II) complex 1 ([MnClP]2, P−=2,3,4,5‐tetrakis(benzo[d]thiazol‐2‐yl)pyrrol‐1‐ide). The reaction process has been studied by assigning a series of intermediates based on time‐dependent mass spectrometry, control experiments, crystallography, and density functional theory (DFT) theoretical calculation. A plausible mechanism involving an unprecedented divergent‐convergent domino sequence has been proposed. Compound S1 could be activated by MnCl2 ⋅ 4H2O via coordination, which divergently produces two intermediates imine II (1‐(benzo[d]thiazol‐2‐yl)‐N‐(benzo[d]thiazol‐2‐ylmethyl)methanimine) and alkene C (1,2‐bis(benzo[d]thiazol‐2‐yl)ethene) through oxidative self‐condensation and free radical coupling followed by elimination, respectively. They could then react with each other convergently via formal [3+2] cycloaddition to give deprotonated tetrasubstituted pyrrole coordinated intermediate [MnClP] after aromatization. Dimerization of [MnClP] produces the final product 1. Three C−C bonds and one C−N bond are formed through this six‐step domino sequence. The corresponding organic skeleton (HP: 2,2′,2′′,2′′′‐(1H‐pyrrole‐2,3,4,5‐tetrayl)tetrakis(benzo[d]thiazole)) has been obtained from 1 and shows a higher fluorescent quantum yield (52 %) than the reported 3,4‐diphenyl substituted analogue 2,2′‐(3,4‐diphenyl‐1H‐pyrrole‐2,5‐diyl)bis(benzo[d]thiazole) (DPB) (42 %). [ABSTRACT FROM AUTHOR]

In order to comparing and explaining the experimental infrared, electronic absorption and emission spectra of tris (4‐methyl‐1‐(1‐methyl‐1H‐benzo [d] imidazol‐2‐yl) −4H‐benzo [d] imidazo[1,5‐a]imidazol‐3‐yl) methyl (L6), density functional theory calculations were performed to systematically study the spectral properties of several species with different electronic states (L6+, L6 and HL6+), as well as the axial substituted derivative with methoxy group (L6‐OCH3). The main peaks in the vibrational, electronic absorption and emission spectra were assigned in detail. Roles of molecular electronic states and axial substitution on the spectral properties are revealed. The calculated spectra are compared with experimental results to distinguish the nature of L6 in crystal and solvent. This work combing experiment and theoretical calculations would be good example for clarifying molecular electronic states and, thus, promising the practice application of such kind of novel molecules. [ABSTRACT FROM AUTHOR]

RE2SiO5 (RE = Yb and Lu) are significant environmental barrier coating (EBC) materials, in which surface and oxygen vacancy play crucial roles in their structural stability and functionality. In this work, the structural configuration and thermodynamics of (1 0 0), (0 1 0), and (0 0 1) surfaces of RE2SiO5 are investigated by first‐principles calculations. The (0 0 1) surface is preferred energetically, which is attributed to the weak bond broken environment and large rare‐earth polyhedron distortion on this surface. Moreover, the formation energies of various oxygen vacancies on the stable (0 0 1) surface are estimated and the optimal location for oxygen vacancies is held by the [SiO4] tetrahedron. The oxygen vacancies are more likely to segregate on the surface because of the lower formation energies on the surfaces compared with those in the bulk. These findings are expected to enable the development of RE2SiO5‐based EBCs by tuning grain size and/or thin film growth orientation. [ABSTRACT FROM AUTHOR]

A facile photoetching approach is described that alleviates the negative effects from bulk defects by confining the oxygen vacancy (Ovac) at the surface of BiVO4 photoanode, by 10‐minute photoetching. This strategy could induce enriched Ovac at the surface of BiVO4, which avoids the formation of excessive bulk defects. A mechanism is proposed to explain the enhanced charge separation at the BiVO4 /electrolyte interface, which is supported by density functional theory (DFT) calculations. The optimized BiVO4 with enriched surface Ovac presents the highest photocurrent among undoped BiVO4 photoanodes. Upon loading FeOOH/NiOOH cocatalysts, photoetched BiVO4 photoanode reaches a considerable water oxidation photocurrent of 3.0 mA cm−2 at 0.6 V vs. reversible hydrogen electrode. An unbiased solar‐to‐hydrogen conversion efficiency of 3.5 % is realized by this BiVO4 photoanode and a Si photocathode under 1 sun illumination. [ABSTRACT FROM AUTHOR]

A facile photoetching approach is described that alleviates the negative effects from bulk defects by confining the oxygen vacancy (Ovac) at the surface of BiVO4 photoanode, by 10‐minute photoetching. This strategy could induce enriched Ovac at the surface of BiVO4, which avoids the formation of excessive bulk defects. A mechanism is proposed to explain the enhanced charge separation at the BiVO4 /electrolyte interface, which is supported by density functional theory (DFT) calculations. The optimized BiVO4 with enriched surface Ovac presents the highest photocurrent among undoped BiVO4 photoanodes. Upon loading FeOOH/NiOOH cocatalysts, photoetched BiVO4 photoanode reaches a considerable water oxidation photocurrent of 3.0 mA cm−2 at 0.6 V vs. reversible hydrogen electrode. An unbiased solar‐to‐hydrogen conversion efficiency of 3.5 % is realized by this BiVO4 photoanode and a Si photocathode under 1 sun illumination. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings (TBCs) play an important role in gas turbines to protect the turbine blades from the high‐temperature airflow damage. In this work, we use first‐principles calculations to investigate a specific class of rare‐earth (RE) aluminates, including cubic‐REAlO3 (c‐REAlO3), orthorhombic‐REAlO3 (o‐REAlO3), RE3Al5O12, and RE4Al2O9, to predict their structural stability, bonding characteristics, and mechanical and thermal properties. The polyhedron structures formed by the Al–O bonds are stronger and exhibit rigid characteristics, whereas the polyhedra formed by the RE–O bonds are relatively weak and soft. The alternating stacking of AlO4 tetrahedra, AlO6 octahedra, and RE–O polyhedra, as well as the selection of RE elements, shows intensive influences on the expected mechanical and thermal properties. The B, G, and E of these four types of aluminates decrease in the order of c‐REAlO3 > o‐REAlO3 > RE3Al5O12 > RE4Al2O9. REAlO3 and RE4Al2O9 are brittle and quasi‐ductile ceramics, respectively, whereas RE3Al5O12 is tailorable. The minimum thermal conductivity is in the range of 1.4–1.5 W m−1 K−1 for c‐REAlO3, 1.3–1.4 W m−1 K−1 for o‐REAlO3, 1.25–1.35 W m−1 K−1 for RE3Al5O12, and 0.8–0.9 W m−1 K−1 for RE4Al2O9. RE4Al2O9 with low thermal conductivity and damage tolerance is predicted to be the potential candidates for next‐generation TBC materials. [ABSTRACT FROM AUTHOR]

The surface structures, bond variations, and segregation of oxygen vacancies play crucial roles in the structural stability and functionality of nanocrystalline rare‐earth zirconate pyrochlores. In this work, the stabilities of (1 0 0), (1 1 0), and (1 1 1) surfaces of pyrochlore A2Zr2O7 (A = La, Ce, Pr, Nd, Pm, Sm, Eu, or Gd) are investigated by first‐principles calculations. Surface reconstruction occurs on (1 1 0) surface with a transition of ZrO6 octahedron to ZrO4 tetrahedron, leading to their large relaxation energies. In combination with the small amount of broken bonds during the surface formation process, the (1 1 0) surfaces are identified having the lowest surface formation energies than the (1 0 0) and (1 1 1) surfaces. Moreover, the reconstructed (1 1 0) surface has characteristics of the segregation of oxygen vacancies. The surface oxygen vacancies have the low migration barriers (<1.2 eV), which are comparable with those in bulk and ensure the long‐distance diffusion of oxygen vacancies in A2Zr2O7. These discoveries provide fundamental insight to the surface structure and related oxygen vacancy behavior, which are expected to guide the optimization of the surface related properties for nanocrystalline rare‐earth zirconates. [ABSTRACT FROM AUTHOR]

The synthesis of aromatic azo compounds from anilines and nitrobenzene usually requires environmentally unfriendly transition metal catalysts. Here, we propose that azobenzene oligomers are formed in surface-enhanced Raman experiments assisted by surface plasmon resonance. The photocatalytic polymerization of p-dinitrobenzene (DNB) and p-phenylenediamine (PDA) to the corresponding azo-like oligomers on silver surfaces is studied by the surface-enhanced Raman spectroscopy and density functional theory. First, the normal Raman and surface Raman spectra of DNB and PDA are simulated and measured. The simulated normal Raman spectra are in good agreement with their solid-state Raman spectra. However, the simulated surface Raman spectra of DNB-Ag10 and PDA-Ag10 complexes are significantly different from the experimental surface-enhanced Raman spectra. We propose that DNBs has a reductive coupling and PDAs undergo an oxidative coupling reaction during SERS experiments. Secondly, the Raman spectra of the possible NN coupling oligomers of DNB and PDA are simulated. They are compared with the SERS spectra of DNB and PDA adsorbed on silver surfaces. Especially, the Raman spectra of p, p′-dinitroazobenzene and p, p′-diaminoazobenzene are in good agreement with the SERS spectra of DNB and PDA adsorbed on silver surface. Finally, two reaction mechanisms are proposed to explain the surface photocatalysis of DNB and PDA. In the solution, the nitro group of DNB can be reduced by the excited hot electrons. DNBs are then converted to p, p′-dinitroazobenzene through multiple proton and electron transfers. In the air and in the presence of O2, O2 is firstly activated through surface plasmon resonance. PDAs are then converted to p, p′-diaminoazobenzene by the generated active oxygen species. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen peroxide (H2O2) production from dioxygen and water is regarded as a promising technology since it can achieve sustainable and green solar‐to‐chemical energy conversion. Herein, oxygen and potassium dual‐heteroatom incorporated polymeric carbon nitride (O/KCN) is rationally designed for H2O2 generation with an ultrahigh rate of 309.44 µM h−1 mg−1, which surpasses that of other C3N4‐based photocatalysts. The enhanced performance can be ascribed to the effective light absorption, fast charge transfer/separation, strong oxygen adsorption, and highly selective two‐electron oxygen reduction reaction (ORR). Density functional theory calculations further confirm that the obtained O/KCN is more favorable than others for electrons migrating from β spin‐orbital to π* orbitals of O2 molecule, thus optimizing O2 molecule activation to promote the formation of intermediate species *OOH and decrease the energy barrier of H2O2 production. This work not only provides in‐depth insights for the photocatalytic H2O2 generation mechanism, but also lays the foundation for further development of highly active photocatalysts for environmental remediation and energy conversion. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of point defects and the oxygen vacancy diffusion in rare earth (RE) silicates is important to evaluate their performance as environmental barrier coatings. In this work, the defect formation energies are calculated and the similar predominant native point defect type, that is, O Frenkel defect, in RE2SiO5 and RE2Si2O7 (RE = Yb and Lu) is uncovered. Furthermore, the nonstoichiometry related defects and phase composition in RE2SiO5 and RE2Si2O7 is also studied. For RE2SiO5, SiRE·+Oi″ or SiRE·+VRE″′ is the predominate defect complex accompanied with the RE2Si2O7 separation under SiO2‐rich condition, while RESi′+VO·· or RESi′+REi··· is favorable under RE2O3‐rich condition. In the case of RE2Si2O7, SiRE·+VRE″′ or SiRE·+Oi″ is the favorable defect complex under SiO2‐rich condition while RESi′+VO·· or RESi′+REi··· dominates the defects, accompanied with the formation of RE2SiO5, under RE2O3‐rich case. Finally, the high oxygen migration barriers are revealed for both RE2SiO5 and RE2Si2O7, indicating the low oxygen permeability in these silicates. These results will not only guide the future performance optimization of RE2SiO5 and RE2Si2O7 through tailoring their composition, but also suggest their potential application as oxidation protective coatings. [ABSTRACT FROM AUTHOR]

Nitrogen‐doped graphitic carbon materials have been widely used as a catalyst support in the methanol oxidation reaction (MOR). In this study, we report the role of three‐dimensionally architectured in‐situ N‐doped vertically aligned carbon nanofibers (VACNF) as a catalyst support for MOR in acidic and alkaline media. The abundant graphitic edge sites at the sidewall of N‐doped VACNF strongly anchor the deposited platinum group metal (PGM) catalysts and induce a partial electron transfer between the PGM catalysts and support. Density Functional Theory (DFT) calculations reveal that the strong metal‐support interaction substantially increases the adsorption energy of OH, particularly near the N‐doping sites, which helps to compete and remove the adsorbed intermediate species generated during MOR. The PGM catalysts on N‐doped VACNF support exhibits CO stripping at lower potentials comparing to the commercial Vulcan carbon support and presents an enhanced electrocatalytic performance and better durability for MOR. [ABSTRACT FROM AUTHOR]

Manganese (Mn) nitrides are important nitrogen (N) carriers for small‐scale intermittent ammonia (NH3) synthesis. However, only 3∼8 % of lattice N are converted into NH3. In this study, the geometric and electronic structures of well‐defined Mn4N and Mn2N lattices were altered using transition metal heteroatoms (Cr, Fe, Co, Ni, Mo) to understand the driving force behind lattice N diffusion and extraction. Density Functional Theory (DFT) revealed that the binding of early hydrogenation product (NH) follows a linear relationship with lattice N over a wide range of close‐packed surfaces. But, the binding of NH2 and NH3 are more sensitive to the geometric and electronic structures. Further, the chemical bonding can be quantitatively characterized with the covalency derived from Crystal Orbital Hamiltonian Population (COHP). In the Eley Rideal‐Mars van Krevelan pathway, the overall NH3 formation free energy (ΔGNH3) and lattice N diffusion barrier (Ea) are the respective thermodynamic and kinetic determining factors. Aided by a rate‐determining step (RDS) model, Mn4N modified with Fe, Co, Ni single‐atom dopants all show enhanced rates for NH3 formation. [ABSTRACT FROM AUTHOR]

The pH‐dependent surface‐enhanced Raman spectra of two typical surface sensor molecules p‐mercaptobenzoic acid (PMBA) and p‐mercaptopyridine (PMPY) were simulated by density functional theory calculations. First, the acid dissociation constants and individual surface Raman spectra of PMBA and PMPY were computed and compared with experimental results. It was found that acid dissociation constants calculated by the hybrid implicit‐explicit model and surface‐enhanced Raman scattering (SERS) spectra simulated by the explicit model most closely coincide with experimental results. Then, the pH‐dependent SERS spectra of PMBA and PMPY were obtained by overlaying the SERS of individual acid species and base species multiplied by their molar fractions, which were calculated from the acid dissociation constants. During the deprotonation process of PMBA, the Raman intensity from COOH stretching decreases and the Raman intensity from COO− stretching increases. During the protonation process of PMPY, the ν8a mode undergoes a significant blueshift and the relative Raman intensity of ν7a mode decreases. At last, pH calibration curves of PMBA and PMPY were obtained according to the simulated pH‐dependent Raman spectra, in which the logarithmic value of relative Raman intensity of characteristic peaks varies almost linearly with solution pH. [ABSTRACT FROM AUTHOR]

The knowledge of accurate bond strengths is a fundamental basis for a proper analysis of chemical reaction mechanisms. Quantum chemical calculations at different levels of theory have been used to investigate heterolytic Fe-O and Fe-S bond energies of (meta-substituted phenoxy)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4OFp ( 1)] and (meta-substituted benzenethiolato)dicarbonyl(η5-cyclopentadienyl) iron [ m-G-C6H4SFp ( 2)] complexes. In this study, Fp is (η5-C5H5)Fe(CO)2, and G is NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2. The results show that Tao-Perdew-Staroverov-Scuseria and Becke's power-series ansatz from 1997 with dispersion corrections functionals can provide the best price/performance ratio and accurate predictions of Δ Hhet(Fe-O)'s and Δ Hhet(Fe-S)'s. The excellent linear free energy relations [ r = 1.00 (g, 1e), 1.00 (g, 2b)] among the ΔΔ Hhet (Fe-O)'s and δΔ G0 of OH bonds of m-G-C6H4OH or ΔΔ Hhet(Fe-S)'s and Δp Ka's of SH bonds of m-G-C6H4SH imply that the governing structural factors for these bond scissions are similar. And, the linear correlations [ r = −0.97 (g, 1 g), −0.97 (g, 2 h)] among the ΔΔ Hhet (Fe-O)'s or ΔΔ Hhet(Fe-S)'s and the substituent σm constants show that these correlations are in accordance with Hammett linear free energy relationships. The inductive effects of these substituents and the basis set effects influence the accuracy of Δ Hhet(Fe-O)'s or Δ Hhet(Fe-S)'s. The ΔΔ Hhet(Fe-O)'s(g) (1) and ΔΔ Hhet(Fe-S)'s(g)(2) follow the capto-dative Principle. The substituent effects on the Fe-O bonds are much stronger than those on the less polar Fe-S bonds. Insight from this work may help the design of more effective catalytic processes. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The knowledge of accurate bond strengths is a fundamental basis for a proper analysis of chemical reaction mechanisms. Quantum chemical calculations at different levels of theory have been used to investigate heterolytic Feâ€'O and Feâ€'S bond energies of paraâ€substituted phenoxydicarbonyl( η5â€cyclopentadienyl) iron [ pâ€Gâ€C6H4O( η5â€C5H5)Fe(CO)2, abbreviated as pâ€Gâ€C6H4OFp ( 1), where G = NO2, CN, COMe, CO2Me, CF3, Br, Cl, F, H, Me, MeO, and NMe2] and paraâ€substituted benzenethiolatodicarbonyl( η5â€cyclopentadienyl) iron [ pâ€Gâ€C6H4S( η5â€C5H5)Fe(CO)2, abbreviated as pâ€Gâ€C6H4SFp ( 2)] complexes. The results show that BP86 and TPSSTPSS can provide the best price/performance ratio and more accurate predictions in the study of Î' Hhet(Feâ€'O)'s and Î' Hhet(Feâ€'S)'s. The excellent linear freeâ€energy relations [ r = 0.99 (g, 1a), 1.00 (g, 2b)] among the Î'Î' Hhet (Feâ€'O)'s and Î'p ka's of Oâ€'H bonds of pâ€Gâ€C6H4OH or Î'Î' Hhet(Feâ€S)'s and Î'p ka's of Sâ€'H bonds of pâ€Gâ€C6H4SH imply that the governing structural factors for these bond scissions are similar. And the linear correlations [ r = âˆ'0.99 (g, 1g), âˆ'0.98 (g, 2h)] among the Î'Î' Hhet (Feâ€O)'s or Î'Î' Hhet(Feâ€S)'s and the substituent σpâˆ' constants show that these correlations are in accordance with Hammett linear freeâ€energy relationships. The polar effects of these substituents and the basis set effects influence the accuracy of Î' Hhet(Feâ€'O)'s or Î' Hhet(Feâ€'S)'s. Î'Î' Hhet(Feâ€'O)'s(g) ( 1) and Î'Î' Hhet(Feâ€'S)'s(g)( 2) follow the Captoâ€dative principle. The substituent effects on the Feâ€'O bonds are much stronger than those on the less polar Feâ€'S bonds. Insight from this work may help the design of more effective catalytic processes. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]