Code: ThP23	Time Slot/Poster Number: 071	Session: Raman Theory
Raman Spectroscopic Signatures of Noncovalent Interactions Involving Trimethylamine N-oxide (TMAO)
Katherine L. Munroe1; David H. Magers2; Nathan I. Hammer1
1University of Mississippi, Oxford, MS; 2Mississippi College, Clinton, Missisippi
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Summary
Trimethylamine N-oxide (TMAO) has been studied extensively both theoretically and experimentally because of its roles in biological functionality that include promoting the folding of biopolymers and counteracting the denaturing effects of urea. Even though TMAO demonstrates a substantial degree of hydrophobic character, it is highly soluble in water and, in fact, it has been suggested that TMAO’s effectiveness originates in the noncovalent interactions with solvated water molecules in biological media. Here, we study the effects of TMAO on the Raman spectroscopic properties of a number of small micro-solvated molecules including water, methanol, ethylene glycol, and 2-mercaptoethanol both experimentally and theoretically.

Code: ThP23	Time Slot/Poster Number: 072	Session: Raman Theory
Raman and SERS Spectroscopy of N-Methyliminodiacetic Acid (MIDA)-Protected Boronate Esters
Dana N. Reinemann; Ashley M. Wright; Jonathan D. Wolfe; Gregory S. Tschumper; Nathan I. Hammer
University of Mississippi, Oxford, MS
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Summary
N-methyliminodiacetic acid (MIDA)-protected boronate esters represent a new class of reagents that offer great promise in iterative Suzuki-Miyaura cross-coupling reactions. Compared to earlier reagents, the MIDA esters are easily handled and are bench-top stable under air indefinitely, making them very attractive to many synthetic chemists. Here, we study the spectroscopic properties of the key structural component common to this new molecular class – the B-N dative bond. This is accomplished by comparing Raman and surface-enhanced Raman (SERS) spectra of methylboronic acid MIDA ester and 1-naphthylboronic acid MIDA ester to the results of high level electronic structure calculations.

Code: ThP23	Time Slot/Poster Number: 073	Session: Raman Theory
Ab-initio Study Of Zone Centre Phonons In MB6 (M=La, Ce, Sm)
Hem Gupta; Sonu Kumar
Indian Institute of Technology, New Delhi, New Delhi, India
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Summary
Ab-initio study of zone centre phonons in rare-earth hexaborides, MB6, has been made using self-consistent density functional method based on norm-conserving pseudo-potentials and numerical atomic orbitals as basis set. Calculated values of zone centre phonons are in fair agreement with the experimental results.

Code: ThP23	Time Slot/Poster Number: 074	Session: Raman Theory
Raman Spectroscopic Investigations of Noncovalent Interactions between Pyrimidine and Hydrogen Bonded Networks
Ashley M. Wright; Austin A. Howard; Gregory S. Tschumper; Nathan I. Hammer
University of Mississippi, Oxford, MS
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Summary
Noncovalent interactions are prevalent in nature and dictate the physical properties of many important molecular systems. Past spectroscopic studies involving water/pyrimidine mixtures revealed a blue shift of the most prominent Raman peak of pyrimidine, that due to the ring breathing mode. Here, the effects of hydrogen bonding by a number of polar molecules on pyrimidine’s vibrational spectrum are studied using Raman spectroscopy. Experimental spectra are compared to the results of high level quantum mechanical calculations and also to previous results obtained in water/pyrimidine mixtures.