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The ability to study local protein structure and dynamics has been significantly increased by the use of unnatural amino acids containing vibrational reporters that can be genetically incorporated into proteins with site-specificity. The nitrile and azide groups are both effective vibrational reporters due in part to the position of the nitrile symmetric stretch vibration and the azide asymmetric stretch vibration, the sensitivity of these vibrations to local environments, the relatively high extinction coefficients of these vibrations, and the small size of these reporters. Recently, we have expanded the utility of a nitrile-modified phenylalanine unnatural amino acid (UAA) to probe local protein environments through the synthesis of three isotopomers (¹⁵N, ¹³C, ¹³C¹⁵N) of this UAA. The isotopomers permit the unambiguous assignment of the nitrile symmetric stretch vibration in addition to permitting multiple local protein environments to be probed simultaneously. Additionally, we have recently developed a photo-stable azido-modified phenylalanine UAA to effectively probe local protein environments. The synthesis of these UAAs, the genetic incorporation of these UAAs into proteins, and the spectral characterization of the resulting protein constructs will be discussed.