The nature of metallophilic interactions in closed-shell d-d metal complexes.

We have quantum chemically analyzed the closed-shell d-d metallophilic interaction in dimers of square planar [M(CO)X] complexes (M = Ni, Pd, Pt; X = Cl, Br, I) using dispersion-corrected density functional theory at ZORA-BLYP-D3(BJ)/TZ2P level of theory. Our purpose is to reveal the nature of the [X(CO)M]⋯[M(CO)X] bonding mechanism by analyzing trends upon variations in M and X. Our analyses reveal that the formation of the [M(CO)X] dimers is favored by an increasingly stabilizing electrostatic interaction when the M increases in size and by more stabilizing dispersion interactions promoted by the larger X.

Quantitative Analysis of Liver Disease Using MRI-Based Radiomic Features of the Liver and Spleen.

Background: Radiomics extracts quantitative image features to identify biomarkers for characterizing disease. Our aim was to characterize the ability of radiomic features extracted from magnetic resonance (MR) imaging of the liver and spleen to detect cirrhosis by comparing features from patients with cirrhosis to those without cirrhosis.

Methods: This retrospective study compared MR-derived radiomic features between patients with cirrhosis undergoing hepatocellular carcinoma screening and patients without cirrhosis undergoing intraductal papillary mucinous neoplasm surveillance between 2015 and 2018 using the same imaging protocol.

Thermodynamic equilibrium between locally excited and charge-transfer states through thermally activated charge transfer in 1-(pyren-2'-yl)--carborane.

Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2'-yl)--carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive 'mixed' state of 1-(pyren-2'-yl)--carborane are very small, and all three excited states are accessible at room temperature.

One- and two-electron reduction of triarylborane-based helical donor-acceptor compounds.

One-electron chemical reduction of 10-(dimesitylboryl)-,-di--tolylbenzo[]phenanthrene-4-amine (3-B(Mes)-[4]helix-9-N(-Tol)) and 13-(dimesitylboryl)-,-di--tolyldibenzo[,]phenanthrene-8-amine (3-B(Mes)-[5]helix-12-N(-Tol)) gives rise to monoanions with extensive delocalization over the annulated helicene rings and the boron p orbital. Two-electron chemical reduction of and produces open-shell biradicaloid dianions with temperature-dependent population of the triplet states due to small singlet-triplet gaps. These results have been confirmed by single-crystal X-ray diffraction, EPR and UV/vis-NIR spectroscopy, and DFT calculations.

MRI-based radiomic feature analysis of end-stage liver disease for severity stratification.

Purpose: We aimed to develop a predictive model of disease severity for cirrhosis using MRI-derived radiomic features of the liver and spleen and compared it to the existing disease severity metrics of MELD score and clinical decompensation. The MELD score is compiled solely by blood parameters, and so far, it was not investigated if extracted image-based features have the potential to reflect severity to potentially complement the calculated score.

Methods: This was a retrospective study of eligible patients with cirrhosis ([Formula: see text]) who underwent a contrast-enhanced MR screening protocol for hepatocellular carcinoma (HCC) screening at a tertiary academic center from 2015 to 2018.