Chemistry Letters, Vol.31, No.8, 788-789, 2002
Anomalous laser photophoretic behavior of photo-absorbing organic droplets in water
Laser photophoretic behavior of 2-benzylpyridine droplets including molybdenum blue as a photo-absorber was examined in water by irradiating with a cw Nd:YAG laser (1064 nm). The photophoretic velocity of the droplet decreased with increasing its absorptivity. The droplets smaller than 1.5 mum in radius with high absorptivity migrated in the opposite direction against the laser irradiation. This is the first observation of the negative photophoresis in liquid media.