Atomic Interactions at a Distance
نویسنده
چکیده
Van der Waals (vdW) forces are the dominant interactions between neutral particles on nanometer-tomicrometer length scales. This makes their effects ubiquitous in physics, chemistry, and biology: they are, for instance, responsible for the action of detergents, the selfassembly of viruses, and even the ability of geckos to climb flat surfaces. Their existence was first proposed by Johannes Diderik van der Waals in the late 19th century, as he developed an equation of state for gases and liquids that captures the gas-liquid transition and approximates the behavior of the liquid state. To derive his equation, van der Waals modified the ideal gas law by including an attractive interaction between molecules proportional to the inverse square of the gas volume, which suggested that the effective force between two neutral particles scales with their distance R as 1/R6.
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