Analytical Theory

Spectroscopy

Pump–Probe Microscopy: Theory, Instrumentation, and Applications

April 01, 2017

Excited state dynamics provides an intrinsic molecular contrast of samples examined. These dynamics can be monitored by pump probe spectroscopy which measures the change in transmission of a probe beam induced by a pump beam. With superior detection sensitivity, chemical specificity and spatial-temporal resolution, pump probe microscopy is an emerging tool for functional imaging of non-fluorescent chromophores and nanomaterials. This article reviews the basic principle, instrumentation strategy, data analysis methods, and applications of pump probe microscopy. A brief outlook is provided.

Spectroscopy

Book Review: The Concise Handbook of Analytical Spectroscopy Theory, Applications, and Reference Materials

January 01, 2017

Heinz W. Siesler, Emeritus Professor at University of Duisburg-Essen, reviews Jerry Workman’s new book, The Concise Handbook of Analytical Spectroscopy Theory, Applications, and Reference Materials

Spectroscopy

Statistics, Part I: First Foundation

October 01, 2015

We present the first of a short set of columns dealing with the subject of statistics. This current series is organized as a “top down” view of the subject, as opposed to the usual literature (and our own previous) approach of giving “bottom up” description of the multitude of equations that are encountered. We hope this different approach will succeed in giving our readers a more coherent view of the subject, as well as persuading them to undertake further study of the field.

Spectroscopy

More Theory and Practice: The Thorny Problem of Mixtures and More on Straight Chain Alkanes

July 01, 2015

Continuing the theory and practice themes from previous columns, the theory portion of this column will be a discussion of the proper way of handling the infrared spectral interpretation of mixtures. In my opinion, mixtures are the biggest obstacle to interpreting infrared spectra, and I will share with readers five tried-and-true techniques for dealing with them. The practice portion of the column will give the answer to the last installment’s problem, and complete the spectral analysis of straight chain alkanes.

Spectroscopy

Practical Group Theory and Raman Spectroscopy, Part II: Application of Polarization

March 01, 2014

Polarized Raman spectra are presented along with a discussion of the association of the symmetry species of the normal vibrational mode and the depolarization ratio of Raman scattering.

Spectroscopy

Quantum Cascade Lasers for Infrared Spectroscopy: Theory, State of the Art, and Applications

April 01, 2013

Mid-infrared quantum cascade lasers, recently developed and commercialized, have unique properties that advance the analytical capabilities of IR spectroscopy in many ways. Bernhard Lendl of Vienna University of Technology in Austria explains these developments.

Spectroscopy

Vibrational Spectroscopic Imaging: Theory, Application, and Advances

February 19, 2013

An interview with Rohit Bhargava, the winner of the 2012 FACSS/SciX Innovation Award.

Resolution in Mid-Infrared Imaging: The Theory

November 11, 2011

The field of mid-infrared (mid-IR) imaging has made significant developments in recent years, but the theory has not kept pace. Rohit Bhargava, an associate professor of engineering at the University of Illinois at Urbana-Champaign and the associate director of the University of Illinois Cancer Center, recently undertook studies to address that gap. Spectroscopy spoke to him recently about that work.

Spectroscopy

Classical Least Squares, Part IV: Spectroscopic Theory Continued

February 11, 2011

The connection between the mathematics of classical least squares and the graphical displays used to present it is examined in further detail.

Spectroscopy

Classical Least Squares, Part III: Spectroscopic Theory

October 01, 2010

The authors continue their ongoing discussion of classical least squares with a look at spectroscopic theory.