Issue
Europhys. Lett.
Volume 74, Number 1, April 2006
Page(s) 110 - 116
Section Condensed matter: structural, mechanical and thermal properties
DOI http://dx.doi.org/10.1209/epl/i2005-10513-4
Published online 08 March 2006
Europhys. Lett., 74 (1), pp. 110-116 (2006)
DOI: 10.1209/epl/i2005-10513-4

Measuring energies with an Atomic Force Microscope

J. Langer1, I. Díez-Pérez2, F. Sanz2 and J. Fraxedas3

1  Institut für Chemie und Biochemie, Physikalische und Theoretische Chemie Freie Universität Berlin - D-14195 Berlin, Germany
2  Center of Bioelectronics & Nanobioscience and Departament de Química-Física Universitat de Barcelona - Martí i Franquès 1, E-08028 Barcelona, Spain
3  Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) Campus UAB, E-08193 Bellaterra, Spain


received 29 December 2005; accepted in final form 13 February 2006
published online 8 March 2006

Abstract
The elastic and plastic response of ordered inorganic, organic and biological materials involving nanometer-scale volumes in the nano- and low micronewton force range can be characterized by means of an Atomic Force Microscope (AFM) using ultrasharp cantilever tips with radius R typically below $10\un{nm}$. Because the plastic onset can be easily identified, the maximal accumulated elastic energy can be directly determined from the force curves (force F vs. penetration $\delta$ curves), thus giving a realistic estimate of the characteristic energies of the materials. We illustrate the ability of AFMs to determine such energies with the case example of the molecular organic metal TTF-TCNQ (TTF = tetrathiafulvalene, TCNQ = tetracyanoquinodimethane), where the enthalpy of sublimation is obtained.

PACS
68.35.-p - Solid surfaces and solid-solid interfaces: Structure and energetics.
68.37.Ps - Atomic force microscopy (AFM).

© EDP Sciences 2006