Study of a nanoscale water cluster by atomic force microscopy

Abstract

We present a novel method for investigating a nanometric cluster of water molecules, which includes the formation and manipulation of nanometric water, and the measurement of its mechanical properties. The atomic force microscope based on the quartz tuning-fork sensor is employed to form and manipulate the nanometric water, and the theoretical tool of amplitude-modulation atomic force microscopy is used to obtain the elasticity, viscosity and dissipation energy of it. With high vertical resolution less than ∼0.1 nm and high force sensitivity of ∼0.01 N m⁻¹, this tool facilitates the stable formation and manipulation of a nano-water cluster (∼10⁴ molecules) in air without ‘jump-to-contact’ instability, as well as quantitative measurements of its physico-chemical properties.

PACS® numbers: 47.55.nk, 62.10.+s, 68.37.Ps