Table 1. Comparison of Our Results with the Previously Reported Commensurate HBC Structure^a.

structure	epitaxy matrix	a [Å]	Γ [deg]	θ [deg]	temperature [K]	source
RT		14.01(8)	120.00(5)	–8.48(4)	300	LEED fit
LT		13.95(2)	120.00(3)	–8.66(2)	1.2	STM FFT fit
commensurate		13.70	120	–8.95	300/420	LEED (refs 35, 36)

^aAll lattice constants a are based on the epitaxy matrices relative to graphite with a lattice constant of 2.461 Å. Γ = ∠(a₁, a₂) is the unit cell opening angle and θ is the unit cell rotation (cf.Figure 1c). The commensurate matrix is equivalent to the commensurate structures reported in the cited references. Experimental uncertainties of the last significant digit are given in parentheses. The finite experimental accuracy does not imply a rationality of the matrix elements.