This study demonstrates that controlling intra-cluster ligand interactions is important to obtain an assembled structure with the desired connecting structures.

The mixing of heteroelements in metal clusters is a powerful approach to generate new physical/chemical properties and functions. However, as the kinds of elements increase, control of the chemical composition and geometric structure becomes difficult. We succeeded in the compositionally selective synthesis of phenylethanethiolate-protected trimetallic AuAgPd and AuAgPt clusters, AuAgPd(SCHPh) and AuAgPt(SCHPh). Single-crystal X-ray structural analysis revealed the precise position of each metal element in these metal clusters. Reacting with thiol at an elevated temperature was found to be important to direct the metal elements to the most stable positions. The electronic structures of these trimetallic clusters become more discretized than those of the related bimetallic clusters due to orbital splitting.

2-Phenylethanethiolate (PET) and 4-tert-butylbenzenethiolate (TBBT) are the most frequently used ligands in the study of thiolate (SR)-protected metal clusters. However, the effect of difference in the functional group between these ligands on the fundamental properties of the clusters has not been clarified. We synthesized [Au 24 Pt(TBBT) 18 ] 0 , which has the same number of metal atoms, number of ligands, and framework structure as [Au 24 Pt(PET) 18 ] 0 , by replacing ligands of [Au 24 Pt(PET) 18 ] 0 with TBBT. It was found that this ligand exchange is reversible unlike the case of other metal-core clusters. A comparison of the geometrical/electronic structure and stability of the clusters between [Au 24 Pt(PET) 18 ] 0 and [Au 24 Pt(TBBT) 18 ] 0 revealed three things with regard to the effect of ligand change from PET to TBBT on [Au 24 Pt(SR) 18 ] 0 : (1) the induction of metal-core contraction and Au-S bond elongation, (2) no substantial effect on the HOMO-LUMO gap but a clear difference in optical absorption in the visible region, and (3) the decrease of stabilities against degradation in solution and under laser irradiation. By using these two clusters as model clusters, it is expected that the effects of the structural difference of ligand functionalgroups on the physical properties and functions of clusters, such as catalytic ability and photoluminescence, would be clarified. † Electronic supplementary information (ESI) available: Bond lengths, peak positions in SWV curves, additional schemes, characterization of a precursor, photograph of TLC and crystal, ESI mass and XPS spectra, HPLC chromatogram, crystal data of the product. CCDC 1944945. For ESI and crystallographic data in CIF or other electronic format see

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Objective. Primary dysmenorrhea (PD) is a common and high incidence disease in gynecology, which seriously affects the quality of life in young women. Our previous study found that mild moxibustion could treat abdominal pain of PD patients, but the mechanism is still unclear. Therefore, this study aims to partly investigate the treatment mechanism of moxibustion for PD, especially on uterine microcirculation. Methods. Forty 3-month-old Sprague Dawley female rats were randomly divided into four groups, including group A (saline control group, n = 10), group B (control plus moxibustion group, n = 10), group C (PD model group, n = 10), group D (PD. model plus moxibustion group, n = 10). The PD rat model was established by injecting estradiol benzoate and oxytocin. Mild moxibustion on Sanyinjiao (SP6) and Guanyuan (CV4) acupoints was once a day, 20 minutes per time, for 10 consecutive days. A vaginal smear was used to test the estrous cycle of rats. Uterine microvascular thickness was observed by stereomicroscope. And we detected the content of prostaglandin F2α (PGF2α) and prostaglandin E2 (PGE2) in uterine tissue by enzyme-linked immunosorbent assay. Results. Mild moxibustion can enlarge the microvessels, improve the microcirculation disturbance, and relieve the swelling of the uterus in PD rats. During the mild moxibustion intervention, the contents of PGF2α and PGE2 in uterus issues were synchronous increases or decreases and the changes of PGE2 were more obvious, but the changes of uterine microvasculature and morphology caused by the decrease of PGF2α were greater than PGE2. Conclusion. Mild moxibustion at SP6 and CV4 acupoints may relax uterine microvascular obstacle by reducing the content of PGF2α in uterine tissue, improve the microcirculation disorder, and then alleviate the PD rat’s uterine swelling.