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As practiced disciplines, structural chemistry and thermochemistry need not be related. In the current study, the relation is made more evident from among the contents of the journal "Structural Chemistry" (Vol. 14) for the year 2003. The year's articles have been reviewed, giving to most of those appearing therein a thermochemical commentary, "spin" or "slant."

As practiced disciplines, structural chemistry, and thermochemistry need not necessarily be related. Yet such relationships, ranging from minor to very close, can help our overall understanding and detailed analyses of the species and methods under consideration. In the current study, these relations are made more evident from among the contents of the journal "Structural Chemistry" (Vol. 15) for the year 2004. The year's articles have been reviewed, giving to most of those appearing therein a thermochemical commentary, "spin" or "slant." A special emphasis is made on raising questions or noting possible future research topics that arise when looking at the relations noted earlier.

Synchrotron-enhanced Fourier transform infrared (SR-FTIR) is a relatively new method of combining a synchrotron's unrivaled brightness, power, focusability, polarization, and tunability with the well-established analytical approach of a traditional FTIR. Although SR-FTIR photons range from infrared (IR) through soft X-ray, applications and discussions herein are limited to the IR range of the spectrum. A SR-FTIR system detects, interacts with, and examines molecular species that respond to IR photons (IR responsive). Thus, SR-FTIR is able to examine only the lighter elements (i.e., C, N, O, etc.), which are the most common elements found on earth. The ability to study these elements using the superior abilities of SR-FTIR, versus traditional FTIR, is transforming scientific understanding of many species interactions (i.e., biological, organic, etc.). Furthermore, the lighter elements are invisible to the only other synchrotron (SR) category, a relativistic heavy ion collider (RHIC or, colloquially, an atom smasher), which detects heavier elements that are invisible to a SR-FTIR (i.e., Ta, Pt, Au, etc.)

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Computational optimization modeling (COM) is a research method that uses advanced computers and specialized software (e.g., Gaussian) to generate extremely detailed analyses of molecular properties and structures with a goal of depicting models with values for molecular properties that match either (a) selected experimentally determined properties or (b) computationally determined conformers with lowest energies of formation over many properties. Determination and effects of various COM treatments on three series of medium-sized organotin(IV) molecules (a) (C 6 H 4 )S(CH 2 )(Me)(Ph x Cl y Sn) (where x ? y = 3), (b) three R 2 SnCl 2 structures, where x ? y = 2 and R = methyl or phenyl, and (c) MeSnCl 3 and Me 3 SnCl, where Me = methyl were researched relative to X-ray crystallography and solid-state NMR. Also, a reliable COM was determined for a bimolecular organotin(IV) system to compute the energy reduction due to system formation. In summary, this research determined for organotin(IV) molecules: (a) reliable COMs, (b) validation methods, (c) complexities of creating reliable models, (d) comparative analyses of molecules in a series, (e) a substitution method to control intramolecularity and hypercoordination, and (f) pre-optimization COM treatments and pre-optimization conformation changes that may influence final conformations.