RT Journal Article SR Electronic T1 Nanoscale chemical imaging by photoinduced force microscopy JF Science Advances JO Sci Adv FD American Association for the Advancement of Science SP e1501571 DO 10.1126/sciadv.1501571 VO 2 IS 3 A1 Nowak, Derek A1 Morrison, William A1 Wickramasinghe, H. Kumar A1 Jahng, Junghoon A1 Potma, Eric A1 Wan, Lei A1 Ruiz, Ricardo A1 Albrecht, Thomas R. A1 Schmidt, Kristin A1 Frommer, Jane A1 Sanders, Daniel P. A1 Park, Sung YR 2016 UL http://advances.sciencemag.org/content/2/3/e1501571.abstract AB Correlating spatial chemical information with the morphology of closely packed nanostructures remains a challenge for the scientific community. For example, supramolecular self-assembly, which provides a powerful and low-cost way to create nanoscale patterns and engineered nanostructures, is not easily interrogated in real space via existing nondestructive techniques based on optics or electrons. A novel scanning probe technique called infrared photoinduced force microscopy (IR PiFM) directly measures the photoinduced polarizability of the sample in the near field by detecting the time-integrated force between the tip and the sample. By imaging at multiple IR wavelengths corresponding to absorption peaks of different chemical species, PiFM has demonstrated the ability to spatially map nm-scale patterns of the individual chemical components of two different types of self-assembled block copolymer films. With chemical-specific nanometer-scale imaging, PiFM provides a powerful new analytical method for deepening our understanding of nanomaterials.