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The Quantum Mechanics of a Rolling Molecular "Nanocar".

ABSTRACT: We formulate a mathematical model of a rolling "molecular wheelbarrow"-a two-wheeled nanoscale molecular machine-informed by experiments on molecular machines recently synthesized in labs. The model is a nonholonomic system (briefly, a system with non-integrable velocity constraints), for which no general quantization procedure exists. Nonetheless, we successfully embed the system in a Hamiltonian one and then quantize the result using geometric quantization and other tools; we extract from the result the quantum mechanics of the molecular wheelbarrow, and derive explicit formulae for the quantized energy spectrum. We also study a few variants of our model, some of which ignore the model's nonholonomic constraints. We show that these variants have different quantum energy spectra, indicating that in such systems one should not ignore the nonholonomic constraints, since they alter in a non-trivial way the energy spectrum of the molecule.

SUBMITTER: Fernandez OE

PROVIDER: S-EPMC6173740 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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The Quantum Mechanics of a Rolling Molecular "Nanocar".

Fernandez Oscar E OE Radhakrishnan Mala L ML

Scientific reports 20181005 1

We formulate a mathematical model of a rolling "molecular wheelbarrow"-a two-wheeled nanoscale molecular machine-informed by experiments on molecular machines recently synthesized in labs. The model is a nonholonomic system (briefly, a system with non-integrable velocity constraints), for which no general quantization procedure exists. Nonetheless, we successfully embed the system in a Hamiltonian one and then quantize the result using geometric quantization and other tools; we extract from the ...[more]

PMID: 30291255

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The Quantum Mechanics of a Rolling Molecular "Nanocar".

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The Quantum Mechanics of a Rolling Molecular "Nanocar".

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