We present a study on molecular-frame photoelectron angular distributions (MFPADs) of small molecules using circularly polarized synchrotron light. We find that the main forward-scattering peaks of the MFPADs are slightly tilted with respect to the molecular axis. This tilt angle is directly connected to the molecular bond length by a simple, universal formula. We apply the derived formula to several examples of MFPADs of C 1s and O 1s photoelectrons of CO, which have been measured experimentally or obtained by means of modeling. In addition, we discuss the influence of the back-scattering contribution that is superimposed over the analyzed forward-scattering peak in the case of homo-nuclear diatomic molecules such as N.

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http://dx.doi.org/10.1039/d2cp05942hDOI Listing

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