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Entrenched compartmentalisation of curriculum subjects and 'teaching to the test' can leave students with limited understanding of the nature and interaction of disciplines. The necessity of developing future teachers' epistemic insight (EI) and equipping them with strategies to address the gaps between subjects has been pushed to the fore by challenges that emerged during the pandemic. This article examines the extent to which epistemic insight is understood by Initial Teacher Education tutors and features in their programmes as well as their recommendations for increasing the inclusion of multidisciplinary approaches in education, based on qualitative and quantitative research. While initial findings revealed a poor understanding of EI, its importance was broadly acknowledged, and the follow-up survey revealed progress in the form of greater engagement with and inclusion of EI by tutors in teacher education. This research was done in the context of a new inspection framework distinguishing substantive and disciplinary knowledge. [ABSTRACT FROM AUTHOR]

In this paper, the electronic structures of cis- and trans-ClONO and BrONO are studied at the CCSD/aug-cc-pVTZ, CASSCF(14,12)/aug-cc-pVTZ, and B3LYP/aug-cc-pVTZ computational levels. For the Cl-O bond, topological analysis of the electron density field, ρ(r), shows the prevalence of the shared-electron type bond (∇2ρ(3,-1) < 0). The Br-O bond, however, represents the closed-shell interaction (∇2ρ(3,-1) > 0). Topological analysis of the electron localization function, η(r), and electron localizability indicator (ELI-D), ΥDσ(r), shows that the electronic structure of the central N-O bond is very sensitive to both electron correlation improvements (coupled-cluster single double (CCSD), CASSCF, density functional theory (DFT)) and bond length alteration. Depending on the method used, the N-O bond can be characterized as a 'normal' N-O bond with a disynaptic V(N,O) basin (DFT); a protocovalent N-O bond with two monosynaptic, V(N) and V(O), basins (CCSD, CASSCF); or a new type, first discovered for FONO, characterized by a single monosynaptic, V(N) basin (CCSD, DFT). The total basin population oscillates between 0.46-0.96 e (CCSD) and 0.86-1.02 e (CASSCF). The X-O bond is described by the single disynaptic basin, V(X,O), with a basin population between 0.76 and 0.81 e (CCSD) or 0.77 and 0.85 e (CASSCF). Analysis of the localized electron detector distribution for the cis-Cl-O1-N=O2 shows a manifold in the Cl···O2 region, associated with decreased electron density. [ABSTRACT FROM AUTHOR]

The electronic structure of cis- and trans-FONO has been studied using topological analysis of the electron localization function at the B3LYP/aug-cc-pVTZ computational level. In cis-FONO with “normal” F[Single_Bond]O bond length (1.428–1.441 Å), a protocovalent F[Single_Bond]O bonding has been found. The central N[Single_Bond]O bond is “drained off” with the electron density (0.40e and 0.42e) and the terminal N[Single_Bond]O bond resembles an electron-rich single bond (2.13e–2.14e). The F...ONO form with a long F...O bond (1.719 and 1.696 Å) has a diradical character and consists of F and NO2 subunits without clear indications of the covalent bond in the F...O region. [ABSTRACT FROM AUTHOR]

The electronic structure of the B C bond has been studied in 19 molecules using topological analysis of ELF. The boron–carbon bond has covalent-polarized character and is represented by disynaptic attractor V(B,C). Population (M062x) of the B C bond varies between 5.46e for the shortest bond and 1.22e for the longest bond. Analysis of the boron–carbon bond polarity (M062x) shows its formation mainly by the carbon atom. Topological analysis of electron localisation function (ELF) has been applied to study the nature of the B C, B C and B C bonds (1.278–1.645 Å) in 19 molecules using the DFT(M062x) method and 18 molecules using the CCSD method. The boron–carbon bond has a covalent-polarised character and is represented by the bonding disynaptic attractor and the basin, V(B,C). Population of the V(B,C) varies between 1.22 and 5.46e (M062x) or 1.93e and 5.45e (CCSD//CCSD(T)), respectively. The existence of single, double and triple BC bonds is confirmed by the topological results. [ABSTRACT FROM AUTHOR]

Nature of the bonding in isolated XeOF2 molecule and F2OXe...NCCH3 complexes have been studied in the gas phase (0 K) using Quantum Chemical Topology methods. The wave functions have been approximated at the MP2 and DFT levels of calculations, using the APFD, B3LYP, M062X, and B2PLYP functionals with the GD3 dispersion correction. The nature of the formal XeO bond in the XeOF2 monomer depends on the basis set used (all-electron vs. the ecp-28 approximation for Xe). Within the all-electron basis set approach the bond is represented by two bonding attractors, V i = 1,2(Xe,O), with total population of about 1.06e and highly delocalized electron density in both bonding basins. No bonding basins are observed using the ecp-28 approximation. These results shows that the nature of xenon-oxygen is complicated and may be described with mesomeric equilibrium of the Lewis representations: Xe(+)O(−) and Xe(-)O(+). For both the xenon-oxygen and xenon-fluorine interactions the charge-shift model can be applied. The F2OXe...NCCH3 complex exists in two structures: 'parallel,' stabilized by non-covalent C...O and Xe...N interactions and 'linear' stabilized by the Xe...N interaction. Topological analysis of ELF shows that the F2OXe...NCCH3 molecule appears as a weakly bound intermolecular complex. Intermolecular interaction energy components have also been studied using Symmetry Adapted Perturbation Theory. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Topological analysis of the electronlocalization function (ELF)has been carried out for the AuNgX (Ng = Ar, Kr, Xe; X = F, Cl, Br,I) molecules using the wave function approximated by the CCSD, MP2,and DFT(B3LYP, M062X) methods including zero-order regular approximation(ZORA). In the Ng–F bond, the bonding disynaptic attractorV(Ng,F) is missing; therefore, there are no signs of the covalentbinding. The nature of the Au–Ng bond depends on the computationalmethod used. Analysis of the ELF carried out for the AuArF and AuXeFmolecules, with the wave function approximated by the CCSD and MP2methods, shows the V(Au,Ng) attractor possibly corresponding to apartially covalent binding between the gold and noble gas atom. However,its very small basin population (<1e) and a very large value ofthe variance of the basin population suggest that the Au–Ngbond has a very delocalized character. Such bond nature may be relatedto the charge shift concept with a resonance of the Au–+NgX, Au+–NgX hybrids. The weakest Au–Ngbond, in terms of the smallest amount of electron density for theV(Au,Ng) basin, is found for the AuKrF molecule with the CCSD method(0.13e). The MP2 method, however, does not yield any V(Au, Ng) population;hence, the covalent Au–Kr bond is not confirmed. Because theV(Au,Ng) attractor is also not observed with the DFT method, the propercharacterization of the Au–Ng bond requires proper descriptionof correlation effects. Additional studies on the Au2and[AuXe]+molecules, performed at the CCSD and B3LYP levels,exhibit no V(Au,Au) and V(Au,Xe) bonding basins either. [ABSTRACT FROM AUTHOR]

Abstract: Our previous studies revealed three different types of N–O bonding: the ‘normal’ covalent bond, characterized by the bonding V(N,O) basin, the protocovalent bond, characterized by two non-bonding basins, V(N), V(O), and a bond characterized by a non-bonding basin, V(N). The results suggest that the formally single N–O bond, containing no ELF-basins, is possible. Our study confirms its existence in the (CF3)2NO–NO molecule. [Copyright &y& Elsevier]

The article focus on the isomerization of nitrous acid HONO to hydrogen nitryl HNO2. Density functional (B3LYP) and MP2 methods, and a wide variety of basis sets, have been chosen to investigate the mechanism of this reaction. The results clearly show that there are two possible paths: 1) Uncatalysed isomerisation, trans-HONO → HNO2, involving 1,2-hydrogen shift and characterized by a large energetic barrier 49.7 ÷ 58.9 kcal/mol, 2) Catalysed double hydrogen transfer process, trans-HONO + cis-HONO → HNO2 + cis-HONO, which displays a significantly lower energetic barrier in a range of 11.6 ÷ 18.9 kcal/mol. Topological analysis of the Electron Localization Function (ELF) shows that the hydrogen transfer for both studied reactions takes place through the formation of a ‘dressed’ proton along the reaction path.1 Use of a wide variety of basis sets demonstrates a clear basis set dependence on the ELF topology of HNO2. Less saturated basis sets yield two lone pair basins, V1(N), V2(N), whereas more saturated ones (for example aug-cc-pVTZ and aug-cc-pVQZ) do not indicate a lone pair on the nitrogen atom. Topological analysis of the Electron Localizability Indication (ELI-D) at the CASSCF (12,10) confirms these findings, showing the existence of the lone pair basins but with decreasing populations as the basis set becomes more saturated (0.35e for the cc-pVDZ basis set to 0.06e for the aug-cc-pVTZ). This confirms that the choice of basis set not only can influence the value of the electron population at the particular atom, but can also lead to different ELF topology. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010 [ABSTRACT FROM AUTHOR]