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Interaction between a dielectric tip and an ionic crystal. Application to scanning force microscopy on LiF and MgO

✍ Scribed by D. Van Labeke; B. Labani; C. Girard

Publisher: Elsevier Science
Year: 1989
Tongue: English
Weight: 402 KB
Volume: 162
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(89)87065-4

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✦ Synopsis

We present a model for calculating the interaction energy of an ionic crystal and a spherical dielectric tip, applicable to experiments in scanning force microscopy. The repulsive energy is introduced by performing a pairwise summation between the atoms ofthe probe and each atom of the substrate. The attractive energy is separated into a dispersive term and an inductive contribution which takes into account the local field generated by the permanent charges lying at the surface ofthe sample. These contributions arc expanded in the (2D) reciprocal lattice associated with the planes of the crystal. This procedure allows the separation of tbe van der Waals force into two parts describing the continuum character and the corrugation of the surface. Numerical results are proposed for the ( 100 ) face of LiP and MgO.

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Oxygen interaction of CdS-based gas sens

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📂 Article 📅 1995 🏛 Elsevier Science 🌐 English ⚖ 379 KB