Studies on GeF₄ valence and rydberg States by electron impact spectroscopy and ab initio calculations

Electron energy loss (EEL) spectra of GeF₄ have been measured with incident electrons at 100 eV for 5° scattering angle and at 30 eV for 30° scattering angle, while sweeping the energy loss over the range 7.0−18.0 eV. Low-lying excited triplet, singlet, valence, and Rydberg States are investigated and the assignments supported by quantum chemical ab initio calculations. This provides the first comprehensive investigation of all singlet and triplet excited electronic States of Germanium tetrafluoride up to the first ionization energy. The Rydberg series converging to the (lowest) ionization energy limits of GeF₄ are also identified according to the magnitude of the quantum defects (δ).