Stretching dependence of the vibration modes of a single-molecule Pt-H2-Pt bridge

TL;DR

This study investigates how stretching affects the vibrational modes of a single hydrogen molecule bridging platinum electrodes, combining experimental spectroscopy with theoretical calculations to understand its conductance properties.

Contribution

It provides a detailed analysis of vibration mode dependence on stretching in a single-molecule Pt-H2-Pt junction, validated by DFT calculations.

Findings

Three vibrational modes observed via spectroscopy.

Vibrational modes vary systematically with stretching.

Theoretical calculations confirm experimental interpretations.

Abstract

A conducting bridge of a single hydrogen molecule between Pt electrodes is formed in a break junction experiment. It has a conductance near the quantum unit, G_0 = 2e^2/h, carried by a single channel. Using point contact spectroscopy three vibration modes are observed and their variation upon stretching and isotope substitution is obtained. The interpretation of the experiment in terms of a Pt-H_2-Pt bridge is verified by Density Functional Theory calculations for the stability, vibrational modes, and conductance of the structure.