6.2.2. Definition of Effective Properties 3064 6.3. Response Properties to Magnetic Fields 3066 6.3.1. Nuclear Shielding 3066 6.3.2. Indirect Spin−Spin Coupling 3067 6.3.3. EPR Parameters 3068 6.4. Properties of Chiral Systems 3069 6.4.1. Electronic Circular Dichroism (ECD) 3069 6.4.2. Optical Rotation (OR) 3069 6.4.3. VCD and VROA 3070 7. Continuum and Discrete Models 3071 7.1. Continuum Methods within MD and MC Simulations 3072

/pdf/quantum-mechanical-continuum-solvation-models-3edv963g14.pdf

Quantum mechanical continuum solvation models.

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

/pdf/the-hitran-2008-molecular-spectroscopic-database-1ud8clpej3.pdf

The HITRAN 2008 molecular spectroscopic database

Jenny Schneider,*,† Masaya Matsuoka,‡ Masato Takeuchi,‡ Jinlong Zhang, Yu Horiuchi,‡ Masakazu Anpo,‡ and Detlef W. Bahnemann*,† †Institut fur Technische Chemie, Leibniz Universitaẗ Hannover, Callinstrasse 3, D-30167 Hannover, Germany ‡Faculty of Engineering, Osaka Prefecture University, 1 Gakuen-cho, Sakai Osaka 599-8531, Japan Key Lab for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237, China

Understanding TiO2 photocatalysis: mechanisms and materials.

In this work we investigated the antibacterial properties of differently shaped silver nanoparticles against the gram-negative bacterium Escherichia coli, both in liquid systems and on agar plates. Energy-filtering transmission electron microscopy images revealed considerable changes in the cell membranes upon treatment, resulting in cell death. Truncated triangular silver nanoplates with a {111} lattice plane as the basal plane displayed the strongest biocidal action, compared with spherical and rod-shaped nanoparticles and with Ag+ (in the form of AgNO3). It is proposed that nanoscale size and the presence of a {111} plane combine to promote this biocidal property. To our knowledge, this is the first comparative study on the bactericidal properties of silver nanoparticles of different shapes, and our results demonstrate that silver nanoparticles undergo a shape-dependent interaction with the gram-negative organism E. coli.

http://www.omnis-mg.hr/Radovi/EC-oblik-koreja.pdf

Does the antibacterial activity of silver nanoparticles depend on the shape of the nanoparticle? A study of the Gram-negative bacterium Escherichia coli.

Infrared spectroscopy of proteins.

A ray-tracing analysis of cat's-eye retroreflectors for use in active open-path Fourier-transform-infrared (OP/FT-IR) spectrometry and the results of testing f/0.5 and f/1.75 cat's-eye retroreflectors built in our laboratory with a commercial active OP/FT-IR spectrometer are presented. The ray-tracing model is based on the optical characteristics of a commercial single-telescope monostatic OP/FT-IR spectrometer and explores trends in cat's-eye behavior in practical but rigorous field conditions encountered during transportable outdoor use. All mirrors modeled are paraboloids for which the focal ratios of the primary mirror are f/0.5, f/1.75, and f/3. The effect of the focal ratio of the primary mirror, the focal length of the secondary mirror, and the off-axis alignment of the primary and the secondary mirror have been evaluated as a function of path length, including variable input-beam divergence, between the spectrometer and the cat's-eye. The paraboloidal mirrors comprising the primary and secondary of the cat's-eye retroreflectors tested were made in our laboratory by spin casting liquid epoxy-graphite composite mixtures followed by in situ polymerization with no postpolishing.

Design and performance considerations of cat’s-eye retroreflectors for use in open-path Fourier-transform-infrared spectrometry

Silver particles grown on silicon in a galvanic displacement process undergo Ostwald ripening in which small particles merge into bigger ones. In this process the particles are shown by scanning electron microscopy to become smoother. Even though the surface area of the nanoparticles is halved on ripening, the Raman enhancement provided by them is at least five times higher than of the particles that did not undergo the ripening. In several regions, transmission electron microscopy (TEM) images show that the ripened particles resemble agglomerated colloids. In these regions the signal due to surface-enhanced Raman scattering (SERS) is greatly enhanced, suggesting that they are the SERS “hot spots”. The importance of boundaries formed between silver particles to the increased Raman signal is suggested.

Surface-Enhanced Raman Spectroscopy Hot-Spots on Ostwald Ripened Silver Nanoparticles Prepared by Galvanic Displacement

The theory of infrared and Raman spectroscopy is introduced, including factors that control the frequency, intensity, and shape of bands in these spectra. Factors that determine the quantitative aspects of vibrational spectroscopy, including Beer's law, the complex refractive index, and the effect of polarized radiation, are discussed. Finally, the instrumentation for mid-infrared, near-infrared, and Raman spectroscopy is discussed.


Keywords:

vibrational spectroscopy;
mid-infrared;
near-infrared;
Raman;
intensities;
refractive index;
polarization;
Fourier transform infrared;
band intensity;
band width

Introduction to the Theory and Instrumentation for Vibrational Spectroscopy

Several optical designs for GC/FT-IR have been investigated. It was found that reflection losses occurring in the light-pipe cause the solid angle of the emerging beam to be much smaller than that of the input beam. This property permits a very small image at the detector to be achieved since the collection mirror may be mounted well away from the end of the light-pipe. With an optical configuration of this sort, the effect of radiation emitted from the light-pipe saturating the response of the detector is also minimized.

Peter R. Griffiths

Papers

Design and performance considerations of cat’s-eye retroreflectors for use in open-path Fourier-transform-infrared spectrometry

Surface-Enhanced Raman Spectroscopy Hot-Spots on Ostwald Ripened Silver Nanoparticles Prepared by Galvanic Displacement

Introduction to the Theory and Instrumentation for Vibrational Spectroscopy

Optimization of GC/FT-IR Measurements II: Optical Design

Open-path FT-IR spectrometry : is completely unattended operation feasible