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1.
标题化合物C23H27NO6是由对硝基苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得.结构通过单晶X射线衍射法测定,其晶体属于正交晶系,空间群Pca2(1),a=1.296 5(3)nm,b=2.352 5(4)nm,c=2.807 8(5)nm,Mr=413.46,V=8.564(3)nm3,Dc=1.283 g.cm-3,Z=16,μ(Mo Kα)=0.093 mm-1,F(000)=3 520.晶体结构用直接法解出,采用全矩阵最小二乘法对原子参数进行修正,最终得偏离因子为R=0.048 3,Rw=0.118 2.在晶体结构中,存在着两个共轭的烯醇式结构.四个C O键长分别为0.126 3(7),0.130 5(8),0.127 6(7)和0.130 5(8)nm,呈现出明显的平均化趋势.  相似文献   

2.
标题化合物C23H27NO6是由对硝基苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得.结构通过单晶X射线衍射法测定,其晶体属于正交晶系,空间群Pca2(1),a=1.296 5(3)nm,b=2.352 5(4)nm,c=2.807 8(5)nm,Mr=413.46,V=8.564(3)nm3,Dc=1.283 g·cm-3,Z=16,μ(Mo Kα)=0.093 mm-1,F(000)=3 520.晶体结构用直接法解出,采用全矩阵最小二乘法对原子参数进行修正,最终得偏离因子为R=0.048 3,Rw=0.118 2.在晶体结构中,存在着两个共轭的烯醇式结构.四个C-O键长分别为0.126 3(7),0.130 5(8),0.127 6(7)和0.130 5(8)nm,呈现出明显的平均化趋势.  相似文献   

3.
采用水热法合成了一种新型配合物 [Cu2(4,3-pybz)4(H2O)]n (1) (4,3-pybz = 4-吡啶-3-苯甲酸), 通过X-射线单晶衍射测定了晶体结构, 并用元素分析、红外光谱、热分析等技术对其进行了表征. 配合物1属单斜晶系, 空间群C2/c;晶胞参数为:a=1.2004(3) nm,b=1.52305(4)nm, c=2.23362(6) nm, β=95.94°, Z=4,V=4.06173(18) nm3,Mr=937.90,Dc= 1.694 Mg·m-3,F(000)= 2  相似文献   

4.
水溶剂中,在三乙基苄基氯化铵(TEBA)存在下,由3-甲基-1-苯基-1H-吡唑-5(4H)-酮和4-(2, 2-二氰基)苯基氰合成并经N,N-二甲基甲酰胺(DMF)与95%乙醇的混合溶剂重结晶得到化合物C21H15N5O的晶体.其结构通过元素分析、IR 和1HNMR进行了表征,用X射线单晶衍射法测定了该化合物的晶体结构.结果表明,晶体属于三斜晶系,P-1空间群,a=1.291 1(2), b=1.368 7(3), c=1.418 0(2) nm, α=71.564(2)°, β=72.694(3)°, γ=69.926(2)°, Mr=353.38, V=2.182 0(7) nm3, Dc=1.076 g*cm-3, Z=4, μ(Mo Kα)=0.070 mm-1, F(000)=736.晶体结构用直接法解出,经全矩阵最小二乘法修正,最终偏离因子R=0.079 9, Rw=0.128 4.化合物分子中,原子C1,C2,C3,C4,C5 和O1形成一个六元环,该六元环中C1-C2键长为0.135 0(5) nm,表明为双键,此六元环为椅式构象.  相似文献   

5.
5,6-二(2-甲氧基苯胺基)-2,3-吡啶二酮的合成和晶体结构   总被引:1,自引:1,他引:0  
在无溶剂条件下,由3-羟基-2(1H)-吡啶酮与2-甲氧基苯胺在NaIO3作用下合成了5,6-二(2-甲氧基苯胺基)-2,3-吡啶二酮,其结构经1HNMR表征.采用X-射线单晶衍射仪测定了产物的晶体结构,晶体结构属单斜晶系,空间群P21/n,晶胞参数为:a=1.1655(2)nm,b=0.72080(10)nm,c=2.0326(4)nm,α=90°,β=92.17(3)°,γ=90°,V=1.7063(5)nm3,Z=4,F(000)=736,Mr=351.36,Dc=1.368g/cm3,μ=0.098mm-1,R1=0.0587,wR2=0.1365.  相似文献   

6.
采用水热法合成了一种新型配合物[Cu2(4,3-pybz)4(H2O)]n(1)(4,3-pybz=4-吡啶-3-苯甲酸),通过X-射线单晶衍射测定了晶体结构,并用元素分析、红外光谱、热分析等技术对其进行了表征.配合物1属单斜晶系,空间群C2/c;晶胞参数为:a=1.2004(3)nm,b=1.52305(4)nm,c=2.23362(6)nm,β=95.94°,Z=4,V=4.06173(18)nm3,Mr=937.90,Dc=1.694Mg.m-3,F(000)=2072,GOF=1.089,最终偏离因子R1=0.0650.配合物1展现了一个(3,6)连接的三维网络拓扑结构,其中Cu(Ⅱ)作为六连接点,4-吡啶-3-苯甲酸配体分别三连接点和连接器.此外,利用B3LYP方法,在6-31G(d)基组水平上对化合物1进行几何构型优化,在此基础上,采用对称性破损(BS)方法研究了配合物的磁性,计算结果表明配合物1具有弱的反铁磁相互作用.  相似文献   

7.
合成了标题化合物C9H17NOS,它的晶体结构已经用X-射线单晶衍射法测定.晶体属正交晶系,P212121空间群,晶胞参数a=0.670 4 (1) nm,b=0.816 7 (2) nm,c=1.826 7 (4) nm,V=1.000 0 (3) nm3,Z=4,Mr=187.30,Dc=1.244 g/cm3,F(000)=408, μ(MoKα)=0.279 mm-1.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.029 5,wR=0.064 2.结构测定表明标题化合物是单螺化合物.由C(1)、C(2)、C(3)、C(4)、C(5) 和C(6) 构成的六元环取椅型构象, 由C(1)、S、C(7)、C(8) 和N构成的五元环取半椅型构象, 两个环共用的螺原子C(1)用sp3杂化轨道与其他原子成键.晶体结构分析表明存在着分子间氢键.  相似文献   

8.
溴化铜在乙醇中溴化4,4-二甲基-1-芳基-3-戊酮,得到α-溴化产物不经分离直接与硫脲环合制得9种2-氨基噻唑类新化合物,收率21.9%~92.9%.目标物2-氨基噻唑类化合物经核磁谱、红外光谱、质谱测定其结构.用单晶X-射线衍射测定了化合物1g.HBr的晶体结构.化合物1g.HBr晶体属单斜晶系,空间群为P2(1)/c,晶胞参数为:a=0.96 713(5)nm,b=1.558 25(8)nm,c=1.306 87(7)nm,Z=4,V=1.665 34(15)nm3,Dc=1.577 g/cm3,F(000)=800,R1=0.0313,ωR2=0.0757,S=1.024.  相似文献   

9.
通过二碘化钐催化的Bigineli反应合成了5-乙酰基-6-甲基-4-(2-呋喃基)-3,4-二氢嘧啶-2-酮,并采用单晶X-射线衍射法测定了其晶体结构.晶体属单斜晶系,P21/n空间群,a=0.883 7(2)nm,b=0.818 6(2)nm,c=1.483 1(3)nm,β=103.73(5)°,V=1.042 2(4)nm3,M=220.23,Z=4,Dc=1.404 g/cm3,μ(MoKα)=0.104 mm-1,F(000)=464.最终偏离因子为R=0.062 3、wR=0.138 4.  相似文献   

10.
化合物C45H43NO17的晶体,在室温条件下,由[bpy][BF4]和L-(-)-二苯甲酰酒石酸合成并经95%乙醇重结晶而得.其结构通过元素分析、IR和1HNMR进行了表征,用X射线单晶衍射法测定了该化合物的晶体结构.结果表明,晶体属于单斜晶系,P-2(1)空间群,a=0.798 8(6)nm,b=2.748 2(18)nm,c=1.061 0(8)nm,β=101.723(10)°,Mr=869.83,V=2.280(3)nm3,Dc=1.267 Mg/m3,Z=2,μ(Mo Kα)=0.098 mm-1,F(000)=912.晶体结构用直接法解出,经全矩阵最小二乘法修正,最终偏离因子R=0.095 0,Rw=0.2582.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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