  Ionization of polar liquids and glasses often yields metastable electron
centers collectively known as weakly bound (wb) electrons that absorb to the
red of the ground state of the solvated/trapped electron. Formation of these
species is thought to be the initial stage of electron localization in such
media. Although these commonly occurring species have distinctive absorption
spectra, no insight into their structure currently exists. In this Letter, we
address the structure of the wb electron in low-temperature ice-Ih
theoretically, using a combination of mixed quantum-classical (MQC) floating
set of Gaussian orbitals (FSGO) - Metropolis Monte Carlo (MC) method and
embedded cluster density functional theory (DFT) post treatment. The comparison
with the observed properties of the wb electron in ice suggests that this
species is an s-like wavefunction filling a water vacancy.
