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A simple, fast and general protocol for quantitative analysis of X-ray photoelectron spectroscopy (XPS) data provides accurate estimations of chemical species in graphene and related materials (GRMs). XPS data are commonly used to estimate the quality of and defects in graphene and graphene oxide (GO), by comparing carbon and oxygen 1s XPS peaks, obtaining an O/C ratio. This approach, however, cannot be used in the presence of extraneous oxygen contamination. The protocol, based on quantitative line-shape analysis of C 1s signals, uses asymmetric pseudo-Voigt line-shapes (APV), in contrast to Gaussian-based approaches conventionally used in fitting XPS spectra, thus allowing better accuracy in quantifying C 1s contributions from graphitic carbon (sp 2), defects (sp 3 carbon), carbons bonded to hydroxyl and epoxy groups, and from carbonyl and carboxyl groups. The APV protocol was evaluated on GRMs with O/C ratios ranging from 0.02 to 0.30 with film thicknesses from monolayers to bulk-like (>30nm) layers and also applied to previously published data, showing better results compared to those from conventional XPS fitting protocols. Based uniquely on C 1s data, the APV protocol can quantify O/C ratio and the presence of specific functional groups in GRMs even on SiOx, substrates, or in samples containing water.

This tutorial aims to divulge to the chemistry community the information that polymorphism can be directly exploited as a property in a variety of technological applications.

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The resonance energies for electron attachment to the chloromethanes are evaluated by means of bound and continuum multiple scattering Xα calculations. The results closely reproduce the experimental electron transmission spectroscopy data and confirm their previous assignment. Electron transmission and dissociative attachment spectra of monochloroalkanes are also reported, in order to obtain information on the effects of branching at the substituted carbon atom and of alkyl chain length on the resonance and chlorine anion production energies.

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The electron transmission spectra of the fluoro~, bromo~, and iodomethanes (except CH 2 F 2 ) and of some monohaloalkanes are reported. The resonance energies for electron attachment to the halomethanes have also been evaluated by means of bound and continuum multiple scattering Xa calculations, which closely reproduce the low~energy experimental data. A large electron affinity increase is observed on going from the fluorine to the heavier halogen derivatives, while within each series of halides the electron affinity increases with increasing number of halogen atoms. The ground anion state is found to be stable in CHBr 3 , CBr 4 , and in all the iodomethanes except CH31. The fragment anion production, as a function of the electron impact energy, has been measured for some of the compounds under investigation, in order to obtain experimental information on anion states very close to zero energy or slightly stable, which are not accessible in electron transmission.

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