Understanding the nature of a newly developed material is of paramount importance in defining its applications. Some characteristics are inherent to the compound and are considered to be part of its fingerprint, while others can be generated as a result of material design and engineering via various treatment methods. Whether inherent or engineered, the knowledge of chemical and structural characteristics of the material plays a vital role for its use in different areas. This chapter is dedicated to the physical and chemical analyses of samples (known or unknown) via nondestructive spectroscopic techniques whereby each presented technique holds a different mechanism of operation. For instance, Raman spectroscopy (RAMAN) uses the vibration of molecules to provide chemical and structural data, while Fourier transform infrared spectroscopy (FTIR) allows identifying this information through absorption and emission of light in the infrared region. Ultraviolet¿visible (UV¿Vis) spectroscopy determines and quantifies the chemical properties of a sample using absorbed monochromatic light in the ultraviolet and visible regions. X-ray photoelectron spectroscopy (XPS) is widely used to analyze the chemical surface of samples providing chemical state information. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analyzes powder samples to identify chemical compounds. X-ray diffraction (XRD) obtains crystallographic structural information (e.g., crystallite size) from crystalline samples. Lastly, nuclear magnetic resonance (NMR) provides physical, chemical, and biological information about the analyzed samples. For each technique, we present information regarding history, mechanism of operation, advantages, and disadvantages, as well as applications centered around the biomedical areas. Finally, a troubleshooting section describes the most common failures faced when analyzing samples with the abovementioned techniques, possible causes, and solutions offered to each problem.
