Excellent Nonlinear Optical M[M4 Cl][Ga11 S20 ] (M = A/Ba, A = K, Rb) Achieved by Unusual Cationic Substitution Strategy.

The typical chalcopyrite AgGaQ2 (Q = S, Se) are commercial infrared (IR) second-order nonlinear optical (NLO) materials; however, they suffer from unexpected laser-induced damage thresholds (LIDTs) primairy due to their narrow band gaps. Herein, what sets this apart from previously reported chemical substitutions is the utilization of an unusual cationic substitution strategy, represented by [[SZn4 ]S12 + [S4 Zn13 ]S24 + 11ZnS4 ⇒ MS12 + [M4 Cl]S24 + 11GaS4 ], in which the covalent Sx Zny units in the diamond-like sphalerite ZnS are synergistically replaced by cationic Mx Cly units, resulting in two novel salt-inclusion sulfides, M[M4 Cl][Ga11 S20 ] (M = A/Ba, A = K, 1; Rb, 2). As expected, the introduction of mixed cations in the GaS4 anionic frameworks of 1 and 2 leads to wide band gaps (3.04 and 3.01 eV), which exceeds the value of AgGaS2 , facilitating the improvement of high LIDTs (9.4 and 10.3 × AgGaS2 @1.06 µm, respectively). Furthermore, compounds 1 and 2 exhibit moderate second-harmonic generation intensities (0.84 and 0.78 × AgGaS2 @2.9 µm, respectively), mainly originating from the orderly packing tetrahedral GaS4 units. Importantly, this study demonstrates the successful application of the cationic substitution strategy based on diamond-like structures to provide a feasible chemical design insight for constructing high-performance NLO materials.

Open honeycomb frameworks of sulphides AHg4Ga5S12 (A = Rb, Cs) exhibiting infrared nonlinear optical properties.

A crystal structure with a diamond-like anionic framework belongs to a non-centrosymmetric macrostructure due to the aligned arrangement of tetrahedral units, meeting the premise of second-order nonlinear optical (NLO) materials. Herein, two new Hg-based sulphides, namely RbHg4Ga5S12 (1) and CsHg4Ga5S12 (2), which are isostructural and crystallise in the trigonal space group R3, are successfully isolated in sealed silica tubes by a solid-state reaction. The features of their three-dimensional open honeycomb frameworks are attributed to the parallel alignment of tetrahedral MS4 (M is disordered by 0.444 Hg and 0.555 Ga) building motifs, accompanied by Rb+ (or Cs+) reseating in the cavities. Notably, although the band gap values of 1 and 2 are 2.30 and 2.36 eV, separately, their thermal expansion anisotropies (0.15 and 0.41, respectively) are favourable for achieving laser-induced damage thresholds (5.6 and 5.8 times that of AgGaS2 for 1 and 2, respectively). In addition, the strong polarisability of tetrahedral MS4 building motifs in the diamond-like anionic structures is responsible for the promising second-harmonic generation (SHG) intensities (1.1 and 1.8 times that of AgGaS2 for 1 and 2, respectively) in the particle size range of 50-75 µm with non-phase-matchable behaviour at 1910 nm. Furthermore, theoretical investigation elaborates that electron transitions in compounds 1 and 2 mainly occur from valence band S-3p to conduction band Hg-6s and Ga-4s states, demonstrating that the linear and nonlinear optical properties originate primarily from the synergy of tetrahedral MS4 units.

Therapeutic effect and mechanism of breviscapine on cisplatin-induced nephrotoxicity in mice.

OBJECTIVE: To observe the protective effect of breviscapine on mice with cisplatin-induced nephrotoxicity. METHODS: Mice were given a single injection of cisplatin (8 mg/kg, i.p.); then, breviscapine was given to mice at 25 mg/kg and 50 mg/kg doses, respectively, once a day for seven days. Renal tissue structure was observed after animals were sacrificed. Blood urea nitrogen (BUN), serum creatinine (Scr), lipid peroxide (MDA) and superoxide dismutase (SOD) serum levels were detected; and MDA, glutathione peroxidase, and SOD levels in the renal cortex were detected. RESULTS: Compared with the blank control group (BCG), the kidney pathological damage of mice in the model control group (MCG) was more severe. After applying different doses of breviscapine, different degrees of renal injury improvement appeared. Compared with the BCG, the serum levels of Scr and BUN in the MCG increased to (89.92 ± 6.78) µmoL/Land (15.32 ± 4.53) mmoL/L. The differences were statistical significant (P < 0.01). Compared with the MCG, the serum levels of Scr and BUN in the Bre low-dose groups and Bre high-dose groups decreased significantly (P < 0.05). Compared with the BCG, the MDA levels in serum and in the renal cortex in the MCG significantly increased, while the SOD levels significantly decreased. Both the differences were statistically significant (P < 0.01). In the Bre low-dose groups and Bre high-dose groups, MDA levels in serum and in the renal cortex significantly decreased, while SOD and glutathione peroxidase levels in the renal cortex significantly increased, compared with the MCG; and the differences were statistically significant (P < 0.05). CONCLUSIONS: Breviscapine can reduce cisplatin-induced renal toxicity in mice and it's possible through inhibition of renal tubule cell lipid peroxidation and reduces the nephrotoxicity of cisplatin.