Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.1
B. Pal, D. Pradhan, G. D. Nigam
The effect of heavy atoms at fixed special positions on the cumulative distribution function N(z) of the normalised intensity z has been studied under the assumption that the heavy atoms are surrounded by inaccessible volumes which are excluded by light atoms in the unit cell. In an earlier work, the expected value of the random variable - the mean value of the structure factor of the light atoms was assumed to be zero. This restriction has now been removed. It is observed that this has a significant effect on the cumulative distribution function of normalised intensity.
{"title":"Effect of inaccessible volume on intensity statistics — atoms in fixed special positions","authors":"B. Pal, D. Pradhan, G. D. Nigam","doi":"10.1524/ZKRI.1997.212.1.1","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.1","url":null,"abstract":"The effect of heavy atoms at fixed special positions on the cumulative distribution function N(z) of the normalised intensity z has been studied under the assumption that the heavy atoms are surrounded by inaccessible volumes which are excluded by light atoms in the unit cell. In an earlier work, the expected value of the random variable - the mean value of the structure factor of the light atoms was assumed to be zero. This restriction has now been removed. It is observed that this has a significant effect on the cumulative distribution function of normalised intensity.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"58 1","pages":"1 - 4"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81150575","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.9
S. Kek, M. Aroyo, U. Bismayer, C. Schmidt, K. Eichhorn, H. Krane
In this study it is shown that the antiferrodistortive phase transition in titanite, CaTiSiO 5 , is a stepwise process. We report the occurrence of an intermediate phase with Ca-disorder in split positions. Ordering of Ca triggers the displacement of Ti in the antiferroelectric phase at lower temperatures. A group-theoretical analysis for the two-step subduction process is given. The irreducible representation Y 2 + accounts for the intermediate phase A2/a (C2/c) with Ca cations in 8f Wyckoff positions below 825 K as well as for the subduction of the isotropy subgroup P2 1 /a below 496K. A high-symmetry phase with Ca in 4e positions exists only above ca. 825 K. In order to study the stepwise structural changes synchrotron radiation was used to collect X-ray diffraction data at 100 K, 295 K and 530 K on the 4-circle diffractometer at HASYLAB using a wavelength of 0.560(1) A. A total of 2292 reflections were recorded at 100 K, 1540 at 295 K and 1442 at 530 K and reduced to 705 (100 K), 707 (295 K) and 358 (530 K) unique observations respectively (sin θ/λ ≤ 0.611 A -1 for all data sets). Refinements with harmonic displacement parameters converged to R w = 0.038 (100 K), R w = 0.039 (295 K), and R w = 0.045 (530 K). The value for R w at 530 K was further reduced to 0.042 by assuming anharmonic temperature factors for Ca. A final significant improvement of the fit could be achieved for the 530 K data using splitted calcium atoms with occupation probability 0.5 in 8f positions (R w = 0.039). k + l = 2n + 1 Bragg-peaks disapper at 496 K. Between 496 K and 825 K anisotropic diffuse scattering of reflections k + l = odd is observed. APB's and deviations from a statistical distribution of disordered Ca can lead to such diffuse reflections with their intensity extended along b * and c * .
本研究表明，catisio5中抗铁畸变的相变是一个循序渐进的过程。我们报告了在分裂位置出现ca无序的中间阶段。在较低温度下，Ca的排序触发了Ti在反铁电相中的位移。对两步俯冲过程进行了群理论分析。y2 +的不可约表示解释了825k以下8f Wyckoff位置Ca阳离子的A2/a (C2/c)中间相以及496K以下各向同性亚群P2 1 /a的俯冲。Ca在4e位的高对称相位只存在于Ca . 825 K以上。为了研究逐步结构性变化同步加速器辐射被用来收集x射线衍射数据在100 K, 295 K和530 K 4-circle衍射仪在HASYLAB使用波长为0.560 (1)a . 2292反射记录在100 K, 1540年在530 K和295 K和1442年减少到705 (100 K), 707 (295 K)和358 (530 K)分别独特的观察(sinθ/λ0.611≤1对所有的数据集)。调和位移参数的细化结果分别为R w = 0.038 (100 K)、R w = 0.039 (295 K)和R w = 0.045 (530 K)。通过假设Ca的非调和温度因子，530 K时的R w值进一步降至0.042。使用分裂的钙原子在8f个位置上占据概率为0.5 (R w = 0.039)，可以实现530 K数据的最终显著拟合。k + l = 2n + 1布拉格峰在496 k处消失。在496 K和825 K之间，观察到K + l = odd反射的各向异性散射。APB和偏离无序Ca的统计分布会导致这种漫反射，其强度沿b *和c *扩展。
{"title":"The two-step phase transition of titanite, CaTiSiO5: a Synchrotron radiation study","authors":"S. Kek, M. Aroyo, U. Bismayer, C. Schmidt, K. Eichhorn, H. Krane","doi":"10.1524/ZKRI.1997.212.1.9","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.9","url":null,"abstract":"In this study it is shown that the antiferrodistortive phase transition in titanite, CaTiSiO 5 , is a stepwise process. We report the occurrence of an intermediate phase with Ca-disorder in split positions. Ordering of Ca triggers the displacement of Ti in the antiferroelectric phase at lower temperatures. A group-theoretical analysis for the two-step subduction process is given. The irreducible representation Y 2 + accounts for the intermediate phase A2/a (C2/c) with Ca cations in 8f Wyckoff positions below 825 K as well as for the subduction of the isotropy subgroup P2 1 /a below 496K. A high-symmetry phase with Ca in 4e positions exists only above ca. 825 K. In order to study the stepwise structural changes synchrotron radiation was used to collect X-ray diffraction data at 100 K, 295 K and 530 K on the 4-circle diffractometer at HASYLAB using a wavelength of 0.560(1) A. A total of 2292 reflections were recorded at 100 K, 1540 at 295 K and 1442 at 530 K and reduced to 705 (100 K), 707 (295 K) and 358 (530 K) unique observations respectively (sin θ/λ ≤ 0.611 A -1 for all data sets). Refinements with harmonic displacement parameters converged to R w = 0.038 (100 K), R w = 0.039 (295 K), and R w = 0.045 (530 K). The value for R w at 530 K was further reduced to 0.042 by assuming anharmonic temperature factors for Ca. A final significant improvement of the fit could be achieved for the 530 K data using splitted calcium atoms with occupation probability 0.5 in 8f positions (R w = 0.039). k + l = 2n + 1 Bragg-peaks disapper at 496 K. Between 496 K and 825 K anisotropic diffuse scattering of reflections k + l = odd is observed. APB's and deviations from a statistical distribution of disordered Ca can lead to such diffuse reflections with their intensity extended along b * and c * .","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"191 1","pages":"9 - 19"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83448565","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.34
H.-J. Brandt, H. Otto
Cu 6 [Ge 6 O 18 ]. 6 H 2 O is obtained from aqueous solution as a crystalline, greenish-turquoise powder, having space group R3, lattice parameters a =15.0347(4) A and c = 7.9493(2) A, with Z = 18 CuGeO 3 H 2 O formula units per unit cell. The density is d x = 3.88 g cm -3 . X-ray powder diffraction data revealed a crystal structure isotypic with that of the mineral dioptase, Cu 6 [Si 6 O 18 ]. 6 H 2 O. The structure was refined by the Rietveld method to a final residual of R F = 0.036 (R p = 0.067, R wp = 0.088). It consists of sandwiched rings with empty channels down [001]. Isolated and less expanded rings of six corner-sharing GeO 4 tetrahedra alternate vertically with crown-shaped rings of six hydrogen-bonded water molecules. The two ring systems are bonded together by Cu 2+ ions in elongated octahedral coordination of four oxygen atoms and two more distant water molecules. Water can be degassed by heating, leaving Cu 2+ in at least square planar coordination. Once water is removed completely, the less dense compound with lattice parameters a = 14.8763(6) A and c = 7.9761(8) A shows reversible thermochromism from denim-blue at room temperature to rich green at high temperatures, a color which can be frozen by rapid cooling. A crystal-chemical comparison is drawn between Cu 6 [Ge 6 O18]. 6 H 2 O and Cu 6 [Si 6 O 18 ]. 6 H 2 O (dioptase) as well as Pb 6 [Ge 6 0 18 ]. 6 H 2 O, which represents the first example observed with pure [Ge 6 O 18 ] 12- single sechser rings.
Cu 6 [ge6o18]。水溶液中得到的6h2o为绿松石状结晶状粉末，其空间群为R3，晶格参数为a =15.0347(4) a和c = 7.9493(2) a，每单元格的公式单位为Z = 18 cugeo3h2o。密度为dx = 3.88 g cm -3。x射线粉末衍射数据显示其晶体结构与矿物铜6 [Si 6 O 18]的晶体结构相同。采用Rietveld法对结构进行细化，最终残差R F = 0.036 (R p = 0.067, R wp = 0.088)。它由夹层环和空通道组成[001]。由6个共用角的GeO - 4四面体组成的孤立的和扩展较小的环与6个氢键水分子组成的冠状环垂直交替。这两个环系是由Cu 2+离子以四个氧原子和两个更远的水分子的八面体配位连接在一起的。水可以通过加热脱气，使cu2 +至少保持平面的平方配位。一旦水完全除去，晶格参数a = 14.8763(6) a和c = 7.9761(8) a的密度较低的化合物表现出可逆的热变色，从室温下的斜纹蓝到高温下的富绿色，这种颜色可以通过快速冷却而冻结。对cu6 [ge6o18]进行了晶体化学比较。6 h2o和Cu 6 [Si 6 O 18]。6 h2o (dioptase)和pb6 [ge60 18]。这是第一个用纯[ge6o18] 12-单环观察到的例子。
{"title":"Synthesis and crystal structure of Cu6[Ge6O18]*6 H2O, a dioptase-type cyclo-germanate","authors":"H.-J. Brandt, H. Otto","doi":"10.1524/ZKRI.1997.212.1.34","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.34","url":null,"abstract":"Cu 6 [Ge 6 O 18 ]. 6 H 2 O is obtained from aqueous solution as a crystalline, greenish-turquoise powder, having space group R3, lattice parameters a =15.0347(4) A and c = 7.9493(2) A, with Z = 18 CuGeO 3 H 2 O formula units per unit cell. The density is d x = 3.88 g cm -3 . X-ray powder diffraction data revealed a crystal structure isotypic with that of the mineral dioptase, Cu 6 [Si 6 O 18 ]. 6 H 2 O. The structure was refined by the Rietveld method to a final residual of R F = 0.036 (R p = 0.067, R wp = 0.088). It consists of sandwiched rings with empty channels down [001]. Isolated and less expanded rings of six corner-sharing GeO 4 tetrahedra alternate vertically with crown-shaped rings of six hydrogen-bonded water molecules. The two ring systems are bonded together by Cu 2+ ions in elongated octahedral coordination of four oxygen atoms and two more distant water molecules. Water can be degassed by heating, leaving Cu 2+ in at least square planar coordination. Once water is removed completely, the less dense compound with lattice parameters a = 14.8763(6) A and c = 7.9761(8) A shows reversible thermochromism from denim-blue at room temperature to rich green at high temperatures, a color which can be frozen by rapid cooling. A crystal-chemical comparison is drawn between Cu 6 [Ge 6 O18]. 6 H 2 O and Cu 6 [Si 6 O 18 ]. 6 H 2 O (dioptase) as well as Pb 6 [Ge 6 0 18 ]. 6 H 2 O, which represents the first example observed with pure [Ge 6 O 18 ] 12- single sechser rings.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"55 1","pages":"34 - 40"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85245891","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.67
K. Peters, E. Peters, H. Schnering, U. Peters, W. Tochtermann
{"title":"Crystal structure of dimethyl (1R*,5S*,8S*,11R*)- 10-aza-11 -hydroxy-8-dimethoxymethyltricyclo[6.3.1.01.5]dodec-9-ene-9,11-dicarboxylate, C18H27NO7","authors":"K. Peters, E. Peters, H. Schnering, U. Peters, W. Tochtermann","doi":"10.1524/ZKRI.1997.212.1.67","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.67","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"32 1","pages":"67 - 68"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86054821","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.79
C. Hansmann, S. Foro, H. Lindner, H. Fuess,
{"title":"Crystal structure of 7,7,8,8-tetracyanoquinodimethane- 4,6,8-trimethyl-azulene complex, (C6H4)(C3N2)2* (C7H2)(C3H2)(CH3)3","authors":"C. Hansmann, S. Foro, H. Lindner, H. Fuess,","doi":"10.1524/ZKRI.1997.212.1.79","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.79","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"45 1","pages":"79 - 80"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81769336","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.83
P. Prieto, S. Foro, H. Neunhoeffer, H. Lindner
{"title":"Crystal structure of 5-methoxy-3-phenyl-6- (4-phenyl-2,3-diazabutadien-1 -yl)-1,2,4-triazine, (C6H5)CHN2CH(CN2CNC)OCH3(C6H5)","authors":"P. Prieto, S. Foro, H. Neunhoeffer, H. Lindner","doi":"10.1524/ZKRI.1997.212.1.83","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.83","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"68 1","pages":"83 - 84"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74485733","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.5
M. Jacob, K. Larsson, S. Andersson
Certain lipid bilayers in water adapt cubic conformations of hyperbolic geometry, like periodic minimal- or nodal surfaces, and these can be dispersed into particles called cubosomes. The hyperbolic geometry requires a wide span of molecular conformations in this packing environment, and a high degree of mobility in the bilayers is therefore likely in order to provide the packing equilibrium between molecules at the flat points and those at the necks. It is here proposed that the lipid bilayers form standing waves, with the middle of the bilayers represented by the corresponding nodal surface. Transversal vibrations result in a vibration mode and longitudinal in a breathing mode, both of them being more emphasised at the flat points. The standing wave description is extended to cubosome particles, and as examples cubosomes with D-surface internal structure and tetrahedral external boundaries are presented.
{"title":"Lipid bilayer standing wave conformations in aqueous cubic phases","authors":"M. Jacob, K. Larsson, S. Andersson","doi":"10.1524/ZKRI.1997.212.1.5","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.5","url":null,"abstract":"Certain lipid bilayers in water adapt cubic conformations of hyperbolic geometry, like periodic minimal- or nodal surfaces, and these can be dispersed into particles called cubosomes. The hyperbolic geometry requires a wide span of molecular conformations in this packing environment, and a high degree of mobility in the bilayers is therefore likely in order to provide the packing equilibrium between molecules at the flat points and those at the necks. It is here proposed that the lipid bilayers form standing waves, with the middle of the bilayers represented by the corresponding nodal surface. Transversal vibrations result in a vibration mode and longitudinal in a breathing mode, both of them being more emphasised at the flat points. The standing wave description is extended to cubosome particles, and as examples cubosomes with D-surface internal structure and tetrahedral external boundaries are presented.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"4 1","pages":"5 - 8"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75821312","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.77
K. Peters, E. Peters, H. Schnering, V. Koenigstein, W. Tochtermann
{"title":"Crystal structure of (1R*, 10S*,11S*, 13S*)-9-oxo-12,15-dioxatetracyclo[ 6.4.2.110,13.O1,11]pentadeca-8(14)-ene-13,14-dicarboxylate, C19H24O7","authors":"K. Peters, E. Peters, H. Schnering, V. Koenigstein, W. Tochtermann","doi":"10.1524/ZKRI.1997.212.1.77","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.77","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"38 1","pages":"77 - 78"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74775543","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.65
I. Mutikainen, R. Hämäläinen, M. Klinga, U. Turpeinen
{"title":"Crystal structure of tetraaqua(orotato) magnesium(II) hydrate (1/2.5), [Mg(C5H2N2O4)(H2O)4]*2.5 H2O","authors":"I. Mutikainen, R. Hämäläinen, M. Klinga, U. Turpeinen","doi":"10.1524/ZKRI.1997.212.1.65","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.65","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"49 1","pages":"65 - 66"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74021924","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}
Pub Date : 1997-12-01DOI: 10.1524/ZKRI.1997.212.1.50
K. Range, F. Rau, M. Zabel, H. Paulus
{"title":"Crystal structure of nickel tin sulfide (3/2/2), Ni3Sn2S2","authors":"K. Range, F. Rau, M. Zabel, H. Paulus","doi":"10.1524/ZKRI.1997.212.1.50","DOIUrl":"https://doi.org/10.1524/ZKRI.1997.212.1.50","url":null,"abstract":"","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"14 1","pages":"50 - 50"},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89012079","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}
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