Atoms

||Electrons

Atomic level resolution is possible due to the created tunneling current between the STM tip and the sample. The current is measured and displayed as an image. The same method may also be used to charge and move individual atoms.

By arranging two ultra-short laser light pulses, it is found that an electron takes 40 attoseconds to pass through one layer of magnesium atoms.

||Molecular structure

Similar to EDX, a gas electron diffractometer can be used to analyze molecules in their gaseous states. Angstrom precision on electron diffraction and bond lengths are readily achievable (additionally to angle measurements).

||Reactions – chemical

The binding energy of the outer shell electrons determine the chemical reaction affinity. The ionization potential may assist in the quantification of this energy by, for example, laser excitation.

Once atoms combine to form compounds, it may be possible to image their coordination and planar bond structures. In AFM non-contact mode, individual covalent bonds of oligo-(phenylene-1,2-ethynylenes) were imaged as they underwent a series of reaction-induced changes.

||Reactions – mechanical

A force of approximately 42 yoctonewtons (exp-24) is the smallest force measured. This is still four times larger than the Standard Quantum Limit defined by the Heisenberg uncertainty principle which is the most sensitive measurement that can be made. In this measurement, gas of 1200 rubidium atoms was optically trapped by 840 and 860nm wavelengths and chilled to nearly absolute zero. Probe beam at 780nm registered the oscillatory reaction of modulating the 840nm wavelength.

||Reactions – quantum tunneling

In ultra-cold reactions, the activation barriers are too high for the cold atoms and cannot exchange electrons to bind together. These temperatures are near absolute zero at μK or nK. Lasers may be used to trap and hold these slow moving atoms.

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