  Conventional photoemission orbital tomography based on Fourier iterative
method enables us to extract a projected two-dimensional (2D) molecular orbital
from a 2D photoelectron momentum map (PMM) of planar $\pi$-conjugated molecules
in a single-orientation system, while not in a multi-orientation system. In
this work, we demonstrate photoemission orbital tomography for $\pi$-conjugated
molecules with a tight-binding ansatz (linear combination of atomic orbitals).
We analyze 2D PMMs of single-orientation pentacene/Ag(110) and
multi-orientation 3,4,9,10-perylenetetracarboxylic dianhydride/Ag(110) and
reproduce their three-dimensional highest occupied molecular orbitals. We
demonstrate that the PhaseLift algorithm can be used to analyze PMM including
experimental or theoretical uncertainties. With the 2D PMM for pentacene, we
simultaneously optimized the structure and the molecular orbital. The present
approach enables us to extract the three-dimensional orbitals and structures of
existing materials.

Materials Science