Inter- and intra-molecular charge redistributions in H-bonded Cyanuric Acid*Melamine (CA*M) networks: insight from core level spectroscopy and natural bond orbital analysis.

In this work, we elucidate the electronic charge redistributions that occur within the cyanuric acid (CA) and melamine (M) molecules upon formation of the triple H-bond between the imide group of CA and the diaminopyridine group of M. To achieve this, we investigated 2D H-bonded assemblies of M, CA and CA*M grown on the Au(111) surface, using X-ray photoemission (XPS) and near edge X-ray absorption fine structure (NEXAFS) spectroscopies. Compared to the homomolecular networks, the spectra of the mixed sample reveal core level shifts in opposite directions for CA and M, indicating a nearly complementary charge accumulation on the CA molecule and a charge depletion on the M molecule.

B-Spline Solution of the Two-Center Dirac Equation in the Electronic Continuum for Relativistic Molecular Photoionization.

In this work, the two-center Dirac equation is solved numerically using an extension of an adapted B-spline basis set method previously implemented in relativistic atomic calculations (Fischer, C. F.; Zatsarinny, O.

Electronic Structure of Rh and Ir Single Atom Catalysts Supported on Defective and Doped ZnO: Assessment of Their Activity Towards CO Oxidation.

This study investigated the electronic structure of single-atom Rhodium (Rh) and Iridium (Ir) adsorbed on defective and impurity-doped ZnO(0001) surfaces, and assessed their activity towards the CO oxidation reaction. Our findings reveal that surface impurities significantly influence the binding energies and electronic properties of the metal atoms, with Al and Cr serving as particularly effective promoters. While Rh and Ir acquire a positive charge upon incorporation on the unpromoted Zn(0001) surface, adsorption directly on the promoter results in a net negative charge, thus facilitating the activation of both CO and O species.

Impact of 5 waves of COVID-19 on pediatric ophthalmology.

Objective: To characterize the impact of multiple waves of COVID-19 on pediatric ophthalmology at a tertiary care hospital.

Methods: Medical records were reviewed from pediatric patients seen for ophthalmic emergencies at the Montreal Children's Hospital (Montreal, Canada) from 5 COVID-19 periods: March 13 to May 31, 2020; September 20, 2020, to February 21, 2021; March 21 to May 31, 2021; August 17 to November 5, 2021; and December 19, 2021, to January 25, 2022, as well as 2 pre-COVID time periods: March 13 to May 31, in 2018 and 2019).

Results: There was a significant reduction in ophthalmic consultations when comparing pre-COVID to all 5 COVID waves (p < 0.

Oxygen-Promoted on-Surface Synthesis of Polyboroxine Molecules.

We present a protocol for the on-surface synthesis of polyboroxine molecules derived from boroxine molecules precursors. This process is promoted by oxygen species present on the Au(111) surface: oxygen atoms facilitate the detachment of naphthalene units of trinaphthyl-boroxine molecules and bridge two unsaturated boroxine centers to form a boroxine-O-boroxine chemical motif. X-ray spectroscopic characterization shows that, as the synthesis process proceeds, it progressively tunes the electronic properties of the interface, thus providing a promising route to control the electron level alignment.