Physics Today — American Institute of Physics

Water’s rapidly changing hydrogen-bond network links molecular interactions to its unusual bulk properties. The talk introduces correlated vibrational spectroscopy (CVS), which combines higher-order optical measurements, symmetry selection and angular polarimetry to isolate signals from interacting molecules and directly examine low-frequency hydrogen-bond stretching. CVS measurements reveal electronic charge transfer and nuclear quantum effects in water and acidic or basic solutions. Hydroxide donates roughly 8% more negative charge to the network than water, while protons reduce transfer by less than 4%. Nuclear quantum effects weaken hydrogen bonds in pure water by about 10% and change charge transfer in acidic, but not basic, solutions. In acids, charge is accepted locally by a proton and reduced by its delocalization. In bases, donation extends across several hydration shells, beyond the region affected by proton delocalization. The presentation explains how these measurements probe intermolecular correlations and concludes with further applications of CVS.

A semiconductor fabrication case study follows a defect from its initial discovery to a potential root cause. The speakers use wafer maps and graphical exploration to identify patterns, connect manufacturing-process and test measurements, and investigate trends across large datasets. The presentation shows how combining these data can narrow the possible causes of defects or changing yield. Drawing on the speakers’ semiconductor-industry experience, it addresses practical troubleshooting for process, yield, research, test and metrology teams and explains how visual analysis can make complex manufacturing data more useful.