Exploring new molecular science at interfaces by novel nonlinear spectroscopy

在原有ESFG光谱的基础上，我们开发了一系列新型界面选择性非线性电子和振动光谱，如时间分辨ESFG（TR-ESFG）、4阶非线性拉曼（X^<(4)> Raman）、外差检测ESFG（HD-ESFG）和外差检测VSFG（HD-VSFG）。使用这些新方法，我们研究了水界面的基本问题。我们阐明了有效极性、蛋白质的表面变性、染料分子的超快动力学、水界面处的新型氢键以及观察到的水分子在带电水界面处的翻转。

On the basis of our original ESFG spectroscopy, we have developed a group of new interface-selective nonlinear electronic and vibrational spectroscopies such as time-resolved ESFG (TR-ESFG), 4^<th>-order nonlinear Raman (X^<(4)> Raman), heterodyne-detected ESFG (HD-ESFG) and heterodyne-detected VSFG (HD-VSFG). Using these new methods, we studied fundamental problems of water interfaces. We clarified the effective polarity, surface denaturation of a protein, ultrafast dynamics of dye molecule, novel hydrogen bonding at the water interfaces, and observed flip-flop of water molecules at the charged water interfaces.