ten.1021/ja503316p | J. Am. Chem. Soc. 2014, 136, 9094-Journal in the American Chemical Society Table 1. Experimental and Theoretical S Covalency in Mo Bis-dithiolene ComplexesS K-edge XAS complicated [Mo O(bdt)2]IV 2-ArticleDFT S p ( ) 38 59 33 15 53 NA RE (eV)a 0 0.7 -1.three -0.three 0.six NA S p ( ) 31 59 31 ten 38 23 RE (eV) 0 0.7 -1.2 -0.3 0.six two.orbital dxz/dyz dxy/dz2 dyz/dy2(O out of plane +/-) dx2-z2(O in plane +) dx2-y2(O in plane +) dxz(O in plane -)E (eV) 2472.4 2473.1 2471.2 2472.two 2473.0 Not shownDo 1.12 1.36 0.79 0.67 1.02 NAh four four 4 two 2[MoIVO2(bdt)2]2-aRE stands for Relative Energy. We make use of the lowest pre-edge power in [MoIVO(bdt)2]2- as a reference.Figure three. MO diagrams of [MoIVO(bdt)2]2- (left) and [MoVIO2(bdt)2]2- (right). Chosen atoms in [MoVIO2(bdt)2]2- have been removed for clarity.2473.1 eV. There is also a low energy shoulder at 2472.four eV. On the basis of your second derivative of your spectrum (Figure S1A), there is an added peak at 2473.7 eV below the rising edge. When compared with the spectrum on the [MoIV(OSi)(bdt)2]- complicated (Figure 2B), which requires a total of 4 peaks below the edge for any excellent match, the 3 pre-edge featuresin the [MoIVO(bdt)2]2- complicated are shifted to larger energy as a result of the presence on the robust oxo ligand, which destabilizes the energies on the unoccupied Mo d orbitals.2-(2-Bromoethyl)oxirane Purity The [MoVIO2(bdt)2]2- complicated (Figure 2C) features a dominant feature at 2473.0 eV, as well as a clear pre-edge function at 2471.2 eV. From the second derivative (Figure S1B), you will find twodx.doi.org/10.1021/ja503316p | J. Am. Chem. Soc. 2014, 136, 9094-Journal with the American Chemical SocietyArticleFigure 4. Symmetry adapted linear combinations (SALCs) of oxo p and p orbitals plus the d-orbital mixings in the antibonding MOs of bisoxo MoVI bis-dithiolene complicated. The coordinate system is offered inside the upper ideal panel.Formula of Methyl 3-fluoro-5-iodo-2-methylbenzoate additional peaks required at 2472.two and 2473.7 eV. In comparison to the spectrum with the [MoVIO(OSi)(bdt)2]- complicated (Figure 2D), which demands five peaks beneath the edge for a superior fit, all four pre-edge capabilities are again shifted to greater power as a result of the additional oxo ligand in the bisoxo MoVI complicated.PMID:23829314 In comparing the MoVI to the MoIV complexes, the pre-edge capabilities for the [MoVIO2(bdt)2]2- complicated are at reduce power relative to those for the [MoIVO(bdt)2]2- complex. A related low energy function is also observed within the comparison of your [MoVIO(OSi)(bdt)2]- as well as the [MoIV(OSi)(bdt)2]- complexes. The lower pre-edge power for the MoVI complexes is as a consequence of each the presence of an extra unoccupied d-orbital (2 spin holes) for the MoVI relative towards the MoIV complexes, which corresponds for the lowest power peak, and also the increased Zeff of MoVI, which shifts the d-manifold down in energy. The energies and intensities obtained in the fits are given in Table 1. Peak assignments are presented below. 3.1.two. DFT Correlations to XAS Spectra. Spin-unrestricted DFT calculations had been utilised for peak assignments and for quantitative comparisons towards the experimental data. The totally optimized geometric structures are constant using the crystal structures which have bond distances inside 0.04 ? and bond angles inside three?(Figure 1).39 Molecular orbital diagrams for the [MoIVO(bdt)2]2- and [MoVIO2(bdt)2]2- complexes are presented in Figure three. The MO contours for the reference compounds in Figure 1B,D are shown in Figure S2 for comparison. Inside the five-coordinate, square pyramidal [MoIVO(bdt)2]2- complicated, the Mo dx2-y2 orbital is predominantly nonbond.