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Sebastian Vogel Maxim Bykov Elena Bykova Sebastian Wendl Simon D. Kloß Anna Pakhomova Stella Chariton Egor Koemets Natalia Dubrovinskaia Leonid Dubrovinsky Wolfgang Schnick 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9158-9161
The high‐pressure behavior of non‐metal nitrides is of special interest for inorganic and theoretical chemistry as well as materials science, as these compounds feature intriguing elastic properties. The double nitride α‐BP3N6 was investigated by in situ single‐crystal X‐ray diffraction (XRD) upon cold compression to a maximum pressure of about 42 GPa, and its isothermal bulk modulus at ambient conditions was determined to be 146(6) GPa. At maximum pressure the sample was laser‐heated, which resulted in the formation of an unprecedented high‐pressure polymorph, β‐BP3N6. Its structure was elucidated by single‐crystal XRD, and can be described as a decoration of a distorted hexagonal close packing of N with B in tetrahedral and P in octahedral voids. Hence, β‐BP3N6 is the first nitride to contain PN6 octahedra, representing the much sought‐after proof of principle for sixfold N‐coordinated P that has been predicted for numerous high‐pressure phases of nitrides. 相似文献
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Ommid Anamimoghadam James A. Cooper Minh T. Nguyen Qing‐Hui Guo Lorenzo Mosca Indranil Roy Junling Sun Charlotte L. Stern Louis Redfern Omar K. Farha J. Fraser Stoddart 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13916-13921
Reported here is the synthesis, solid‐state characterization, and redox properties of new triangular, threefold symmetric, viologen‐containing macrocycles. Cyclotris(paraquat‐p‐phenylene) ( CTPQT6+ ) and cyclotris(paraquat‐p‐1,4‐dimethoxyphenylene) ( MCTPQT6+ ) were prepared and their X‐ray single‐crystal (super)structures reveal intricate three‐dimensional packing. MCTPQT6+ results in nanometer‐sized channels, in contrast with its parent counterpart CTPQT6+ which crystallizes as a couple of polymorphs in the form of intercalated assemblies. In the solid state, MCTPQT3(.+) exhibits stacks between the 1,4‐dimethoxyphenylene and bipyridinium radical cations, providing new opportunities for the manipulation and control of the recognition motif associated with viologen radical cations. These redox‐active cyclophanes demonstrate that geometry‐matching and weak intermolecular interactions are of paramount importance in dictating the formation of their intricate solid‐state superstructures. 相似文献
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Martin K. Schmitt Dr. Oliver Janka Prof. Dr. Rainer Pöttgen Dr. Christopher Benndorf Dr. Marcos de Oliveira Jr. Prof. Dr. Hellmut Eckert Dr. Florian Pielnhofer Amadeus-Samuel Tragl Prof. Dr. Richard Weihrich Dr. Bastian Joachim Prof. Dr. Dirk Johrendt Prof. Dr. Hubert Huppertz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6549-6553
We report on the first thoroughly characterized molybdenum borate, which was synthesized in a high-pressure/high-temperature experiment at 12.3 GPa/1300 °C using a Walker-type multianvil apparatus. Mo2B4O9 incorporates tetrahedral molybdenum clusters into an anionic borate crystal structure—a structural motif that has never been observed before in the wide field of borate crystal chemistry. The six bonding molecular orbitals of the [Mo4] tetrahedron are completely filled with 12 electrons, which are fully delocalized over the four molybdenum atoms. This finding is in agreement with the results of the magnetic measurements, which confirmed the diamagnetic character of Mo2B4O9. The two four-coordinated boron sites can be differentiated in the 11B MAS-NMR spectrum because of the strongly different degrees of local distortions. Experimentally obtained IR and Raman bands were assigned to vibrational modes based on DFT calculations. 相似文献
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