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Updated: May 30, 2026

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
1/t pressure and fermion behaviour of water in two dimensions
Taekyun Ha1, Sukmin Chung, M Y Choi
1Department of Physics, POSTECH, Pohang 790-784, Republic of Korea.
Abstract:
A variety of metal vacuum systems display the celebrated 1/t pressure, namely power-law dependence on time t, with the exponent close to unity, the origin of which has been a long-standing controversy. Here we propose a chemisorption model for water adsorbates, based on the argument for fermion behaviour of water vapour adsorbed on a stainless-steel surface, and obtain analytically the power-law behaviour of pressure, with an exponent of unity. Further, the model predicts that the pressure should depend on the temperature T according to T(3/2), which is indeed confirmed by our experiment. Our results should help elucidate the unique characteristics of the adsorbed water.
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