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The analogy between boron clusters and polycyclic hydrocarbons has emerged as a fascinating concept in chemistry in recent years.Typical examples include B12/C6H6,B16 2-/C10H8,B18H6 2+/C10H10,B22 2-/C14H10,and B36/C24H12.1,2 In this work at PBE0/6-311+G* level,we predict the existence of planar B23H6-/0 which appear to be the hydroboron analogs of pyrene C16H10.Both the elongated D2h B23H6 and C2v B23H6-are found to possess almost perfectly planar structures,geometrically similar to D2h C16H10.More importantly and interestingly,their eight canonical molecular orbitals(CMOs)have an exact one-to-one correspondence with that of D2h C16H10.Detailed adaptive natural density partitioning(AdNDP)analyses further indicate that C2v B23H6-is antiaromatic in nature,with 4 island π bonds(2×4c-2e π and 2×5c-2e π)at each corner and 4 totally delocalized π bonds(4×23c-2e π)covering the whole molecular surface conforming to the 4n Hückel rule,again similar to pyrene(see Fig.1).D2h B23H6 has essentially the same bonding pattern.B23H6-/0 are therefore the hydroboron analogs of pyrene.To facilitate their future photoelectron spectroscopy(PES)characterizations,we simulate the PES spectrum of C2v B23H6-at TD-DFT.B23H6-appears to have the calculated vertical detachment energy of VDE=3.51 eV(which corresponds to the electron affinity of B23H6),followed by two broad bands between 4.2-5.3 eV and 5.8-6.4 eV,respectively.