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K2CaB8O26H24单晶结构和溶解转化机理 总被引:6,自引:0,他引:6
本研究报道K2CaB8O26H24复盐单晶的X射线衍射结构测定结果。结构式为K2Ca[B4O5(OH)4]2·8H2O,属正交晶系(orthorhombic),空间群P212121,晶胞参数a=1.1550(2)nm,b=1.2484(2)nm,c=1.6580(2)nm。分子体积V=2.3906(6)nm^3,Z=4,Dc=1.792g·cm^-3,μ=0.720mm^-1,F=(000)=1320。使用振动光谱表征了该复盐的基团特征。根据该复盐在水中的溶解过程,讨论了溶解转化机理,得出该复盐为组分不同步溶解,溶解产物属于无定形态,后转化为晶态Ca[B3O3(OH)5]·4H2O. 相似文献
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Johannes Reisch Raouf A. Hussain Bernt Krebs Mechtild Dartmann 《Monatshefte für Chemie / Chemical Monthly》1990,121(11):941-944
Summary C15H24O2,M=236.2, monoclinic, P 21,a=7.229(7),b=14.925 (9),c=6.235 (9) Å, =92.40 (9)°,V=672.1 Å3,T=–133 °C,Z=2,D
x=1.17 g cm–3. The X-ray diffraction analysis of this sesquiterpenoid fromCarissa opaca confirmed the previously proposed constitution of the isolate and, furthermore, allowed precise NMR assignment.
Naturstoffchemie, 100. Mitt.: Die Struktur des Carissons, C15H24O2
Zusammenfassung C15H24O2,M=236.2, monoklin, P 21,a=7.229 (7),b=14.925 (9),c=6.235 (9) Å, =92.40 (9)°,V=672.1 Å3,T=–133 °C,Z=2,D x=1.17 g cm–3. Die Röntgenstrukturanalyse dieses Sesquiterpenoids ausCarissa opaca bestätigte die bereits vorgeschlagene Struktur und erlaubte ferner eine genaue NMR-Zuordnung.相似文献
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Bisphenoxatelluronium dinitrate is monoelinie, P21/c: a = 11.638(4), b = 28.266(8), c = 8.546(3) å, β = 119.73(2)°, z = 4 at t = 22°. All atoms including hydrogen were located. The two ring systems, I and II, are folded along their Te-O axes, 147° and 163°, respectively. The average ring bond distances are: Te-C = 2.091, C-C = 1.377, C-O = 1.370 Å. Each Te is bonded to one NO3 group, Te1-ON1 = 2.485(5), Te2-ON4 = 2.393(4) Å, and an oxygen bridge connects the ring systems, Te1-OB = 1.966(4), Te2-OB = 2.001(4) Å, Te1-OB-Te2 = 125.0(2)°. The bond distances and angles of the structure are compared to those of related compounds. 相似文献
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