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The near-edge X-ray absorption fine structure (NEXAFS) spectra and the X-ray photoelectron spectroscopy (XPS), as well as the geometrical structures of two C isomers (C(16), C(17)) and their corresponding chlorinated derivatives (C(16) Cl, C(17)Cl) which were newly purified have been investigated by the density functional theory (DFT). The variations of molecular structure, electronic structure and simulated spectra for C isomers after chlorination have been illustrated. Then, the above-mentioned C isomers and their chlorinated derivatives have been identified by the NEXAFS and XPS spectra which show the dependence on the local structure. Furthermore, we have also traced the source of the features in the total spectra by the spectral exploration of each component, which is very helpful for the further study of newly captured fullerene isomers and their derivatives. In this manuscript, we have performed first-principles simulation of the C1s X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine structure spectra (NEXAFS) for two C86 fullerene isomers and the related chlorinated species. The variations of molecular structure, electronic structure and simulated spectra for C86 isomers after chlorination have been illustrated. The above-mentioned C86 isomers and their chlorinated derivatives were identified by the NEXAFS and XPS spectra which show strong dependence on the local structure. Furthermore, we have also traced the source of the features in the total spectra by the spectral exploration of each component. The investigations on newly synthesized fullerenes and derivatives are effectively valuable and stimulative for the experimental researches in future. [ABSTRACT FROM AUTHOR]

Isomers of 1-nitroso-3-nitro-1,2,4-triazol-5-one-2-oxide are of interest in the contest of high explosives and were found to have true local energy minima at the hybrid DFT-B3LYP/aug-cc-pVDZ level. The optimised structures, vibrational frequencies and thermodynamic values for triazol-5-one-N-oxides have been obtained in the ground state. Kamlet–Jacob equations were used to evaluate the performance of model compounds based on the predicted density and the calculated heat of explosion. The detonation properties (D = 10.15–10.46 km/s,P = 50.86–54.25 GPa) of designed compounds were found to be promising compared with 1,3,5-trinitro-1,3,5-triazine (D = 8.75 km/s,P = 34.7 GPa), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (D = 8.96 km/s,P = 35.96 GPa), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (D = 9.20 km/s,P = 42.0 GPa) and octanitrocubane (D = 9.90 km/s,P = 48.45 GPa). The replacement of secondary hydrogen by nitroso group appears to be a particularly promising area for investigation since it may lead to the desirable consequences of higher heat of explosion, higher density and thus detonation performance. [ABSTRACT FROM AUTHOR]

Two supramolecular isomers, {[Cd2(pda)2(1,10'-phen)2]H2O}n (1) and {[Cd2(pda)2(1,10'-phen)2]4-H2O}n (2) (1,10'-phen= 1,10-phenanthroline, pda = phenylenediacrylate dianion), have been synthesized and characterized by single-crystal X-ray analysis. Complex 1 exhibits a 3D network constructed from 1D rod-shaped secondary building units, while 2 shows a 3D, twofold interpenetrated framework. There exists a reversible transformation between the pair of isomers: when yellow block crystals of 1 are treated under microwave irradiation, colorless plate crystals of 2 are formed; in turn, if crystals of 2 are dissolved in water and left undisturbed about two weeks at room temperature, crystals of 1 reappear. Fluorescence properties of 1 and 2 have also been studied. [ABSTRACT FROM AUTHOR]