This seminar will consist of three practice talks for the MRS Fall meeting. Tim will first talk about an experimental determination of the free energy of formation of GaN from its elements. In his second talk, he will present growth of ZnGeN2 single crystals and their micro-Raman spectra, which will be compared to Tula’s calculations of these spectra. Tula will describe the calculation of phonons and related infrared and Raman spectra in the family of II-IV-N2 nitrides with II=Zn, IV=Si,Ge, and Sn. His talk will focus on infrared reflectance spectra on ZnSiN2 and the trends of the phonon spectra in this series of materials.