The secular determinants obtained in the previous paper are solved for the energy levels which are important in the absorption spectra of the normal complex ions, leaving the crystalline field strength as a parameter. The values of B and C (Racah's parameters) there needed are determined from the observed spectra of free ions or in some cases by extrapolation. The f -values of the transitions which connect the energy levels calculated are estimated and compared with the observed intensities. The difference of the spectral width among absorption bands and lines is also considered using the energy diagram obtained. Following the assignments determined by the above considerations, the calculated positions of lines and bands are rather in good agreement with the experimental data in divalent ions [MX 6 ] 2+ (M=Cr, Mn, Fe, Co, Ni), when we adjust the crystalline field parameter D q suitably. In trivalent ions [MX 6 ] 3+ (M=Ti, V, Cr, Mn, Fe), it is necessary besides the adjustment of D q to use smaller values ...

On the absorption spectra of complex ions. II

The molecular chemical structure of poly(methyl methacrylate) (PMMA) surface has been studied by sum frequency generation (SFG) vibrational spectroscopy. By using various methods, we have shown that reflected SFG spectra of PMMA collected in our experiments only come from the polymer/air interface, not from the polymer/substrate or the bulk polymer. These SFG spectra are dominated by the vibrational bands from the ester methyl group. Ranges of orientation and orientation distribution of the ester methyl group on the PMMA surface have been deduced. The antisymmetric stretching vibrational band of the alpha methyl group has been detected on the PMMA surface. Analysis shows that the alpha methyl groups are lying down on the surface. The methylene group has not been observed in SFG spectra. For comparison, we have also studied surface chemical structures of poly(methyl acrylate) (PMA) and dimethyl succinate by SFG.

Molecular Chemical Structure on Poly(methyl methacrylate) (PMMA) Surface Studied by Sum Frequency Generation (SFG) Vibrational Spectroscopy

Silver(I) bindss srongly with sulfur(II –) in inorganic and organic species, resulting in picomolal aqueous dissolved concentrations. For sulfur species found in the environment, Ag(I)–S(II) bonding forms a linear di-coordinate arrangement, – S–Ag–S–, which results in long zigzag chains in inorganic (minerals) and organic (thiolate) complexes. Silver(I) forms the neutral complex AgHS0 at low concentration of S(II –) and Ag(I). Polynuclear complexes form in solution above micromolal concentrations of S(II –). Silver(I) polysulfides may be significant at elevated S(II –). A number of organic mercaptans (thiols) are found in anoxic sediments in nanomolal to micromolal levels and these can act as ligands for Ag(I). The surprisingly limited, known properties of Ag(I) complexes (thiolates) of environmental mercaptans are reviewed. In these thiolate complexes in the solid phase, single crystal X-ray diffraction shows that the –S(R)–Ag –S(R)– chains condense to form sheets that further link through silver–silver interactions to create a network, or slab of silver and sulfur atoms. From nuclear magnetic resonance spectroscopic evidence, zigzag chains also form in the solution phase and aggregate in a random manner to form colloids, which are the predominant form of Ag(I) in solution. The most crucial and important aspect of Ag(I) thiolate chemistry is the rapid exchange of Ag(I) among thiolates. This process is a mechanism whereby Ag(I) can transfer onto, or off, particulate materials or the cells of an organism. Silver(I) thiolates also react rapidly with H2S or HS− as ligands to form Ag2S, but the reverse process is poor because of the high aqueous insolubility and stability of A2Ss. This reaction represents a possible final fate for any Ag(I) thiolate formed in natural waters, as well as any Ag(I)–S(II –) species.

https://setac.onlinelibrary.wiley.com/doi/pdf/10.1002/etc.5620180103

Structural chemistry and geochemistry of silver-sulfur compounds: Critical review

Dual Targeted Delivery of Doxorubicin to Cancer Cells Using Folate-Conjugated Magnetic Multi-Walled Carbon Nanotubes

https://onlinelibrary.wiley.com/doi/epdf/10.1002/aenm.201903696

Highly Efficient Perovskite Solar Cells Enabled by Multiple Ligand Passivation

Spectra analysis of the XPS core and valence energy levels of polymers by an ab initio mo method using simple model molecules

Analysis of valence XPS of (CH2CHR)n (R = H, CH3, OH and F), (CH2CH2NH)n and (CH2CH2O)n polymers by the semiempirical HAM/3 MO method using the n-mer (n = 2, 3, 4, 5) model

C1s spectra of molecules [CH2=CH(COOH), CH2=CH-COOCH3, CH2=C(CH3)COOCH3, CH3-CH(CH3)COOCH3] in gas and fifteen polymers [(CH2-CHR)n (R=H, CH3, OH, OCH3, COCH3, COOH, OCOCH3, COOCH3), ((CH)k-O)n (k=1–4), (CHR-CO-O)n (R=H, CH3), and (CH2-C(CH3)COOCH3)n] in X-ray photoelectron spectroscopy (XPS) were simulated from Koopmans’ theorem by ab initio MO calculations of HONDO7 program using the model oligomers. The calculated C1s spectra were obtained using Gaussian lineshape functions of each fixed linewidth of 0.54 and 1.3 eV for the gas molecules and the oligomers, respectively. The theoretical spectra showed fairly good accordance with the experimental spectra, although the shifted values were used as 14.4 and 21.0 eV for core C1s energy levels of the gas molecules and the model oligomers, respectively. The difference between the shifted values (21.0 and 14.4 eV) approaches to the WD (5.2–6.4 eV) of ten polymers as obtained by deMon density-functional calculations using model molecules with scaled-pVTZ basis set. This is due to the relation of solid effects between the experimental core-electron binding energies of polymers and theoretical MO eigenvalues of the oligomer models, as stated in the previous work.

/pdf/simulation-of-c1s-spectra-of-c-and-o-containing-polymers-in-ouce0vog6t.pdf

Simulation of C1s Spectra of C- and O-Containing Polymers in XPS by Ab Initio MO Calculations Using Model Oligomers

C1s X-ray photoelectron spectra of ten polymers [(CH2-CH2-NH)n, (CH2-CHR)n (R=CN, CONH2, F, OCOCF3, COOCH2CF3, Cl), (CH2(CH2)3CH2-CONH)n, (CH2-CX2)n (X=F, Cl)] were simulated from Koopmans’ theorem by an ab initio molecular orbital (MO) calculations of HONDO7 program using the model molecules. The theoretical spectra showed fairly good accordance with the experimental spectra, although we used the energy shifted value and the linewidth of a Gaussian lineshape function for each core C1s MO value as 21.0 eV and 1.3 eV, respectively. The core-electron binding energies (CEBEs) of C1s for model molecules of polymers [(CH2-CH2-NH)n, (CH2-CHR)n (R=CN, F, Cl), (CH2-CX2)n (X=F, Cl)] were calculated by deMon density functional theory program with scaled polarized valence triple-zeta (scaled-pVTZ) basis set. The WD (sum of work funktion and other energy effects) of the polymers was evaluated as 5.2–6.4 eV from the difference between the calculated CEBEs of the model molecules and the experimental CEBEs of the polymers.

/pdf/analysis-of-c1s-spectra-of-n-o-and-x-containing-polymers-in-1qfriqd4kt.pdf

Analysis of C1s Spectra of N-, O-, and X-Containing Polymers in X-Ray Photoelectron Spectroscopy by Ab Initio Molecular Orbital Calculations Using Model Molecules

Simulation of XPS of Poly(vinyl alcohol), Poly(acrylic acid), Poly(vinyl acetate), and Poly(methyl methacrylate) Polymers by an Ab Initio MO Method Using the Model Molecules

Kazunaka Endo

Papers

Spectra analysis of the XPS core and valence energy levels of polymers by an ab initio mo method using simple model molecules

Analysis of valence XPS of (CH2CHR)n (R = H, CH3, OH and F), (CH2CH2NH)n and (CH2CH2O)n polymers by the semiempirical HAM/3 MO method using the n-mer (n = 2, 3, 4, 5) model

Simulation of C1s Spectra of C- and O-Containing Polymers in XPS by Ab Initio MO Calculations Using Model Oligomers

Analysis of C1s Spectra of N-, O-, and X-Containing Polymers in X-Ray Photoelectron Spectroscopy by Ab Initio Molecular Orbital Calculations Using Model Molecules

Simulation of XPS of Poly(vinyl alcohol), Poly(acrylic acid), Poly(vinyl acetate), and Poly(methyl methacrylate) Polymers by an Ab Initio MO Method Using the Model Molecules