  Using angle-resolved photoemission spectroscopy (ARPES), we study the effect
of the so-called herringbone reconstruction of Au(111) on the dispersion of the
free electron-like surface state. While earlier ARPES investigations have only
reported a minor interplay of the surface state dispersion and the underlying
reconstruction, we show that the uniaxial lattice distortion and the thereby
changed reciprocal lattice for the first atomic layer leads to distinct surface
state dispersions around the first order reciprocal lattice points of the three
domains, creating a constant energy surface resembling a trefoil knot. The
findings resolve the long-standing discrepancy between, on one hand, the
reconstruction-induced surface state modifications reported in scanning
tunnelling microscopy and first principle calculations and, on the other hand,
their conspicuous absence in photoemission.
