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Temperature dependence of the lattice constants and the structure of Mn11Ge8 at 295 and 116 K Mn11Ge8在295和116 K时晶格常数和结构的温度依赖性
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1984-08-01 DOI: 10.1107/S0108768184002287
T. Ohba, N. Watanabe, Y. Komura
{"title":"Temperature dependence of the lattice constants and the structure of Mn11Ge8 at 295 and 116 K","authors":"T. Ohba, N. Watanabe, Y. Komura","doi":"10.1107/S0108768184002287","DOIUrl":"https://doi.org/10.1107/S0108768184002287","url":null,"abstract":"A 295 K, cristallisation dans Pnam avec a=13,214, b=15,880 et c=5,0905 A, Z=4; affinement jusqu'a R=0,0326. La structure a ete affinee egalement a 116 K. La variation en fonction de la temperature des parametres cristallins montre l'apparition d'une discontinuite a 160 K, temperature de la transition magnetique etat ferromagnetique faible→etat antiferromagnetique. Bien que la symetrie cristalline ne change pas, les parametres de position au-dessus et en dessous de 160 K montrent des modifications non uniformes des distances interatomiques. Les densites de deformation le long de la liaison Mn−Mn varient considerablement de 295 a 116 K","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"7 1","pages":"351-354"},"PeriodicalIF":0.0,"publicationDate":"1984-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79514222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 25
Structures of the p-xylylenediammonium chloride and calcium hydrogensulfate adducts of the cavitand 'cucurbituril', C36H36N24O12 C36H36N24O12对二甲基氯化铵和硫酸氢钙加合物的结构
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1984-08-01 DOI: 10.1107/S0108768184002354
W. A. Freeman
{"title":"Structures of the p-xylylenediammonium chloride and calcium hydrogensulfate adducts of the cavitand 'cucurbituril', C36H36N24O12","authors":"W. A. Freeman","doi":"10.1107/S0108768184002354","DOIUrl":"https://doi.org/10.1107/S0108768184002354","url":null,"abstract":"Structure determinations of two crystalline adducts of the cavitand cucurbituril, a cyclic hexameric dimethanoglycoluril of possible catalytic importance, are reported. Crystal data are also reported for 11 other adducts. Cucurbituril is a hexagonal cage with an internal cavity of diameter -5.5 A accessed by portals of diameter -4,~. In the p-xylylenediammonium chloride adduct of cucurbituril [C36H36N24 O 12.N H2 C H2 C6H4C H2 N H2.2 HCI. 10H20, Mr = 1386-1, F(000)= 1412, ~ =2.16cm -~, monoclinic, P2j/n, a=12.071(4), b=15.757(4), c= 14.485 (6) A, /3 =91.98 (3) °, V= 2753 (2) A 3, D,, = 1.63, Dx(Z = 2) = 1.67 gcm -3] the p-xylylenediammonium ion is a guest inside the cucurbituril cage. The structure was refined to R = 0.0624 based on 3694 independent observed reflections collected at 302 K using Mo Ka radiation. The second adduct","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"84 1","pages":"382-387"},"PeriodicalIF":0.0,"publicationDate":"1984-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87382987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 102
On the relationship between the mean plane and the least‐squares plane of an N‐membered puckered ring 关于N元皱环的平均平面与最小二乘平面的关系
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1984-08-01 DOI: 10.1107/S0108768184002391
H. Essén, D. Cremer
{"title":"On the relationship between the mean plane and the least‐squares plane of an N‐membered puckered ring","authors":"H. Essén, D. Cremer","doi":"10.1107/S0108768184002391","DOIUrl":"https://doi.org/10.1107/S0108768184002391","url":null,"abstract":"Discussion du role d'un plan de reference pour la description des molecules a cycle gauche. Presentation et comparaison de deux tels plans: le plan par moindres carres et le plan moyen. Presentation d'une methode simple de calcul du premier evitant l'equation seculaire. Obtention des conditions de coincidence des deux plans. Les avantages de l'approche de plan moyen sont soulignes","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"37 1","pages":"418-420"},"PeriodicalIF":0.0,"publicationDate":"1984-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87541646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 16
Crystal chemistry of oxide–chalcogenides. II. Synthesis and crystal structure of the first bismuth oxide–sulfide, Bi2O2S 氧化物-硫族化合物的晶体化学。2第一氧化硫化铋Bi2O2S的合成及晶体结构
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1984-04-01 DOI: 10.1107/S010876818400183X
E. Koyama, I. Nakai, K. Nagashima
{"title":"Crystal chemistry of oxide–chalcogenides. II. Synthesis and crystal structure of the first bismuth oxide–sulfide, Bi2O2S","authors":"E. Koyama, I. Nakai, K. Nagashima","doi":"10.1107/S010876818400183X","DOIUrl":"https://doi.org/10.1107/S010876818400183X","url":null,"abstract":"Synthese hydrothermale a partir d'un melange stœchiometrique de Bi 2 O 3 et Bi 2 S 3 avec une solution NaOH a 10% comme solvant, a 673 K et 98 MPa. Cristallisation dans Pnnm avec a=3,874, b=11,916 et c=3,840 A, Z=2; affinement jusqu'a R=0,057. Antiprisme carre autour de Bi. Les liaisons Bi-O formant des tetraedres OBi 4 partageant des aretes pour former une couche BiO perpendiculaire a b. Les atomes S lient les couches en une structure bidimensionnelle. Discussion des relations structurales etroites avec Bi 2 O 2 Se, UOS et les oxyhalogenures de Bi","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"42 1","pages":"105-109"},"PeriodicalIF":0.0,"publicationDate":"1984-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89896744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 40
A Crystal Structure Refinement from Laue Photographs taken with Synchrotron Radiation 用同步辐射拍摄的Laue照片的晶体结构改进
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1983-10-01 DOI: 10.1107/S0108768183002931
I. Wood, P. Thompson, J. C. Matthewman
{"title":"A Crystal Structure Refinement from Laue Photographs taken with Synchrotron Radiation","authors":"I. Wood, P. Thompson, J. C. Matthewman","doi":"10.1107/S0108768183002931","DOIUrl":"https://doi.org/10.1107/S0108768183002931","url":null,"abstract":"","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"50 1","pages":"543-547"},"PeriodicalIF":0.0,"publicationDate":"1983-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79036832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 33
Charge distribution and atomic thermal vibration in lead chalcogenide crystals 硫系铅晶体中的电荷分布与原子热振动
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1983-06-01 DOI: 10.1107/S0108768183002463
Y. Noda, S. Ohba, Shoichi Sato, Yoshihiko Saito
{"title":"Charge distribution and atomic thermal vibration in lead chalcogenide crystals","authors":"Y. Noda, S. Ohba, Shoichi Sato, Yoshihiko Saito","doi":"10.1107/S0108768183002463","DOIUrl":"https://doi.org/10.1107/S0108768183002463","url":null,"abstract":"Charge distribution in crystals of lead chalcogenides, PbX (X = S, Se and Te), has been studied by X-ray diffraction. The structure of PbX is of the rock salt type: cubic, Fm3m, a = 5.934 (1), 6.128 (1) and 6.462 (1)A for PbS, PbSe and PbTe, respectively. Final agreement factors for PbS, PbSe and PbTe were R = 0.015, 0.011 and 0.015 for 144, 147 and 130 independent reflections, respectively. The direct integration of charge density, the observed atomic scattering factors, and the population analysis of the valence electrons unanimously indicated that the Pb atom is negatively charged. This observation suggests predominant covalency for the chemical bond in lead chalcogenide crystals. No overlap density was observed in the deformation density map. The bonding electrons in these crystals may be delocalized like free electrons in metals. The thermal parameters of the Pb atoms were found to be larger than those of the chalcogen atoms and the ratio Bpb/B x increases in the order: PbS < PbSe < PbTe. Anharmonic thermal vibration of the Pb atom was detected in the difference electron density maps. A positive peak of 2 (0.3) e A -3 was observed in the (111) direction at 0.4 A from the Pb nucleus for all three compounds. Its height was reduced to 1 (0-3) e A -3 by introducing anharmonic potential parameters for the Pb atom.","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"76 1","pages":"312-317"},"PeriodicalIF":0.0,"publicationDate":"1983-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79282670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 60
The structure of the ribodinucleoside monophosphate guanylyl‐3',5'‐cytidine as its ammonium octahydrate salt 核糖体核苷的结构以单磷酸胍- 3′，5′-胞苷为其八水铵盐
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1983-02-01 DOI: 10.1107/S0108768183002074
A. Aggarwal, S. Islam, R. Kuroda, M. Sanderson, S. Neidle, H. Berman
{"title":"The structure of the ribodinucleoside monophosphate guanylyl‐3',5'‐cytidine as its ammonium octahydrate salt","authors":"A. Aggarwal, S. Islam, R. Kuroda, M. Sanderson, S. Neidle, H. Berman","doi":"10.1107/S0108768183002074","DOIUrl":"https://doi.org/10.1107/S0108768183002074","url":null,"abstract":"The crystal and molecular structure of an ammonium octahydrate salt of the ribodinucleoside monophos-phate guanylyl-3',5'-cytidine (CIgH24NsOI2P) has been determined by X-ray methods, and refined to a final R of 0.111 for 1197 observed reflections. The salt crystallizes in space group C2 with cell dimensions a -- 20.987 (6), b = 16.470 (4), c = 9.566 (1) fit and fl = 94.36 (2)°; Z = 4 for a calculated density of 1.50 Mg m -3 and #(Cu Ka) = 1.19 mm -1. The unit-cell dimensions are very similar to those of the sodium salt [Rosenberg, Seeman, Day & Rich (1976). J. Mol. Biol. 104, 145-167]; however, the two structures are non-isomorphous. Conformational features of the ammonium salt are as expected for an RNA-like Watson-Crick base-paired duplex.","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"38 1","pages":"98-104"},"PeriodicalIF":0.0,"publicationDate":"1983-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79135473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 17
Nucleic acid binding drugs. VII. Molecular-mechanics studies on the conformational properties of the anti-cancer drug daunomycin: some observations on the use of differing potential-energy functions 核酸结合药物。7。抗癌药物道诺霉素构象性质的分子力学研究:利用不同势能函数的一些观察
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1983-02-01 DOI: 10.1107/S0108768183002098
S. Islam, S. Neidle
{"title":"Nucleic acid binding drugs. VII. Molecular-mechanics studies on the conformational properties of the anti-cancer drug daunomycin: some observations on the use of differing potential-energy functions","authors":"S. Islam, S. Neidle","doi":"10.1107/S0108768183002098","DOIUrl":"https://doi.org/10.1107/S0108768183002098","url":null,"abstract":"The conformation of the anti-cancer drug daunomycin \u0000has been investigated in detail by potential-energy \u0000calculations. The flexibility around the ether linkage, \u0000connecting the anthracycline chromophore and the \u0000amino sugar group, has been evaluated using several \u0000types of potential-energy function. The results largely \u0000support the hypothesis that the crystallographically \u0000observed conformation is the most stable one, although \u0000considerable detailed variation with respect to potential \u0000function was found.","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"57 1","pages":"114-119"},"PeriodicalIF":0.0,"publicationDate":"1983-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85722340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 14
The Geometry of the Reactive Site and of the Peptide Groups in Trypsin, Trypsinogen and its Complexes with Inhibitors 胰蛋白酶、胰蛋白酶原及其与抑制剂配合物中活性位点和肽基团的几何结构
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1983-01-18 DOI: 10.1107/S010876818300275X
M. Marquart, J. Walter, J. Deisenhofer, W. Bode, R. Huber
{"title":"The Geometry of the Reactive Site and of the Peptide Groups in Trypsin, Trypsinogen and its Complexes with Inhibitors","authors":"M. Marquart, J. Walter, J. Deisenhofer, W. Bode, R. Huber","doi":"10.1107/S010876818300275X","DOIUrl":"https://doi.org/10.1107/S010876818300275X","url":null,"abstract":"","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"3 1","pages":"480-490"},"PeriodicalIF":0.0,"publicationDate":"1983-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89524097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 501
Aqua(3,7-diaza-2,7-nonadiene-2,8-dicarboxylato-O,O',N,N')copper(II)
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry Pub Date : 1982-12-15 DOI: 10.1107/S0567740882010930
A. Pajunen, S. Pajunen
{"title":"Aqua(3,7-diaza-2,7-nonadiene-2,8-dicarboxylato-O,O',N,N')copper(II)","authors":"A. Pajunen, S. Pajunen","doi":"10.1107/S0567740882010930","DOIUrl":"https://doi.org/10.1107/S0567740882010930","url":null,"abstract":"","PeriodicalId":6887,"journal":{"name":"Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry","volume":"36 1","pages":"3093-3095"},"PeriodicalIF":0.0,"publicationDate":"1982-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73768690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
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