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Abstract Starting from the planar molecule 1,3,5-trihydroxybenzene, Duet al.reported synthesizing one of a couple of possible 2D materials: graphenylene or 3-carbophene.[1] 3-carbophene is a member of a novel class of two-dimensional covalent organic framework, [N]-carbophenes (carbophenes). Using a high throughput method, we computed the formation energies and conduction properties of 3-, 4-, 5-, and 6-carbophenes with hydroxyl (OH), carbonyl (CO), nitro (NO2), amine (NH2), carboxyl (COOH) functional groups replacing hydrogen terminating agents. Five hundred and nine structures with randomly picked motifs, with functionalizations from a single functional group per cell to fully functionalized were studied. Our results demonstrate a negatively sloped linear relationship between the degree of functionalization and formation energy when the type of functional group and type of carbophene are held constant. The decrease in formation energy with functionalization makes Du’s synthesis of functionalized 3-carbophene more creditable. The type of carbophene, type of functional group, and the degree of functionalization all play a role in the band structure of the materials. For example, CO functional groups may lead to a mid- gap state pinned to the Fermi level, whereas the other functional groups studied keep the semiconducting nature of pristine carbophene. Thus, because carbonyl functional groups are often present in defected carbon systems, care should be taken to limit the amount of oxygen in carbophene devices where the band gap is important. Thus, this work strengthens the hypothesis of Junkermeier et al.’s hypothesis thatDu et al.synthesized 3-carbophene and not graphenylene.[2] 

Molecular data of functionalized carbophenes, gas molecules, and gas molecules adsorbed by functionalized carbophenes. All data was produced using density functional tight-binding theory. The data is divided into three text files, each containing the data in the edn extensible data format. A fourth file is an example job script used for creating a DFTB+ input file and running the code on the Mana cluster at the University of Hawaiʻi at Mānoa. Version 1 of this data contained incorrect adsorption energies of CO2 molecules into the pores of the functionalized carbophenes. The errors came from accidentally using the total energy of CO2 as computed in DFTB+ using Universal Force Field parameters for the long-range energy corrections. In contrast, the data set used DFTB+ with Grimme’s D3 dispersion corrections. In Version 2, we corrected the adsorption energy values in the Gas_molecules_in_functionalized_carbophenes.txt records. The file Gas_molecules.txt now includes records for N2 and O2 which were used in computing the formation energies recorded in Gas_molecules_in_functionalized_carbophenes.txt. In creating producing Version 2, we accidentally missed five records. In Version 3, we added those five records back into Gas_molecules_in_functionalized_carbophenes.txt.