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A concise roadmap for using computational chemistry programs (i.e., Gaussian 03W) to predict the color of a molecular species is presented. A color-predicting spreadsheet is available with the online material that uses transition wavelengths and peak-shape parameters to predict the visible absorbance spectrum, transmittance spectrum, chromaticity diagram, and the standard 24-bit color values, sRGB, at several theoretical concentrations. The technique is demonstrated on azulene derivatives and phenolphthalein. The use of this color-prediction spreadsheet in our introductory chemistry lectures and the physical chemistry laboratory is described along with the applicable topic areas. The theory behind color prediction is explained, but the tool is well-suited for novice users. It has been successful in increasing student engagement with the concepts of spectroscopic absorbance and transmittance while introducing the unfamiliar concepts of standard color spaces. (Contains 4 tables, 5 figures, and 1 scheme.)

Abstract.--Two cotton wipe treatments were developed, and a commercial colorimetric wipe was evaluated with the goal of improving airline security screening of suspect articles for chemical oxygen generators (COG) and [...]

High-resolution Fourier-transform infrared spectra of Al(BH4)3 and Al(BD4)3 were obtained for low-pressure samples at room temperature. Results indicated only wide vibrational bands with no resolved rotational structure. The BH bridge stretching and the BH2 deformation areas were also analyzed at 0.001/cm resolution through tunable infrared diode laser spectroscopy for samples cooled to about 10 K in a multipass, slit expansion. Results showed near continua, with much more crowding than predicted by nonrigid rotor simulations based on boron isotopic shifts.

Undergraduate computational chemistry can be significantly enhanced through the use of Gaussian for Windows, allowing students to explore ab initio computations and the effects of varied calculational levels and orbital choices. Free-standing personal computers have advantages over mainframes in that they do not require computer accounts, have quick processors and do not have batch queues. An experiment using Gaussian for Windows to calculate the diatomic molecule HCl's electronic and structural properties is provided.

A colorimetric analysis of a conventional spectrophotometric laboratory exercise applying a spreadsheet program for color analysis is demonstrated.

The photolytic degradation and radical production rates in TATB are studied as a function of 24 different combinations of humidity, temperature, and illumination. A substantial amount of radicals can be generated with UV light, and efforts are being made to modify EPR spectrometer so that TATB can be irradiated in the EPR cavity to measure the initial rates of radical production.

The article presents the systematic process of generating absorbance and transmittance spectra of molecular species over a range of theoretical concentrations. It notes that color prediction spreadsheet is suited for the introduction of chemistry lessons on color. Moreover, the accurate predictive colorimetry process is illustrated with indicating the colors of phenolphthalein and nine azulene derivatives. It states that the vitality of Beer-Lambert law to the absorbance spectrum is exemplified by the concentration multiplier and students can easily see the linear dependence in the simulated series of absorbance spectra. Furthermore, the visual ramification of azulene's functional group changes serve as good test to the use of molecular modeling and color determination method.

The article discusses the spectrophotometric path to the 24-bit color code's development so that it would be more objective than digital photography in terms of color determination. Digital photography has always depended on hard-to-control factors such as brightness correction and scene illumination. Consequently, after the photograph's white point correction with the use of the ImageJ brightness control, the values of the digital image red, green, and blue became similar to the spectrophotometrically determined values of the red, green, and blue.