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231.
232.
Andrew Streitwieser Robert S. McDowell Rainer Glaser 《Journal of computational chemistry》1987,8(6):788-793
A variety of basis sets have been used for geometric and electronic structure studies. Electronic effects were measured using integrated spatial electron populations (ISEP). The two largest basis sets used, 6-31G* and DZ+P, give significantly different results. Use of two d-orbital sets (6-31G*[dd]) or decontraction of the 2sp shell on phosphorus has little further effect. d-Orbitals on oxygen are required for consistent electronic structure results, and d-orbitals on fluorine have a small but significant effect. Use of diffuse functions, required for anions, is not recommended with small basis sets on neutral molecules. Large negative charges (≈?1.5) on oxygen are given by all of the larger basis sets by the ISEP procedure and indicate that the PO bond in these compounds is largely semi-polar. The best simple symbolic representation of phosphine oxide is H3P+? 0?, rather than H3P?0. 相似文献
233.
Raimund Marx Nikolas Pomplun Wolfgang Bermel Heinz Zeiger Frank Engelke Amr F. Fahmy Steffen J. Glaser 《Magnetic resonance in chemistry : MRC》2015,53(6):442-447
The realization of an all‐heteronuclear 5‐qubit nuclear magnetic resonance quantum computer is reported, from the design and synthesis of a suitable molecule through the engineering of a prototype 6‐channel probe head. Full control over the quantum computer is shown by a benchmark experiment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
234.
235.
Walter Glaser 《Zeitschrift für Physik A Hadrons and Nuclei》1935,94(11-12):677-691
236.
237.
Edm Thiele Theodor Posner E. Thon P. N. Raikow und Leo Glaser 《Fresenius' Journal of Analytical Chemistry》1904,43(10):637-638
Ohne Zusammenfassung 相似文献
238.
239.
Thorsten Glaser 《Nachrichten aus der Chemie》2006,54(10):1050-1050
240.
Sonja Tragl Katharina Gibson Jochen Glaser Greta Heydenrych Gernot Frenking Viola Duppel Arndt Simon H.‐Jürgen Meyer 《无机化学与普通化学杂志》2008,634(15):2754-2760
Solid state metathesis reactions between cyanuric chloride and C–N–H or alkali metal–(B–)C–N compounds, respectively, were carried out in the temperature range between 150 °C to 500 °C, studying intermediate stages of reactions and targeting the formation of carbon nitride materials by elimination of HCl or alkali metal chlorides. Although cyanuric chloride was reacted with quite a number of different reaction partners such as melamine, cyanamide, lithium nitride, lithium or sodium carbodiimide, lithium nitridoborate or sodium dicyandiamide, always the same intermediate compounds appeared in the reactions mixtures. Colorless, needle‐shaped crystals of the tertiary amine N(C3N3Cl2)3 ( 1 ) were obtained at temperatures around 200–250 °C. Temperatures as high as 400 °C yielded yellow, plate‐like crystals of the heptazine compound C6N7Cl3 ( 2 ). At even higher temperatures, the reaction products were of poorer crystallinity, but evidence of the formation of another crystalline intermediate was given by X‐ray powder diffraction and electron diffraction experiments. This third intermediate is assumed to be a tertiary amine, quite similar to 1 , however, having heptazine ligands instead of triazine ligands and is assigned with the formula N(C6N7Cl2)3 ( 3 ). Theoretical calculations were performed for the structures and the vibrational spectra of 1 and 3 . Theoretical calculations and a structure refinement based of X‐ray powder diffraction data yielded a plausible structural model for compound 3 . 相似文献