Carla M. Uribe-Rincón, Mohammad Mangir Murshed, Thorsten M. Gesing
The presence of ns2 stereo-chemical active lone electron pairs (LEPs) causes asymmetric atomic environments around a given p-block cation, leading to change the crystal chemistry of a respective system. Here we report a series of mullite-type compounds to understand at what extend Sr2+ replaces the stereochemical active Pb2+ cation in (Pb1−xSrx)MnBO4. Each member of the solid solution has been synthesized by conventional solid-state method. The polycrystalline samples are characterized using X-ray powder diffraction followed by Rietveld refinement. Substitution of Pb2+ with Sr2+ leads to contraction of the a lattice parameter with slight elongation in the b and c direction. For a difference of 1 pm of the ionic radius between Sr2+ and Pb2+, the cell volume contracts about 4 % between the end members as the spatial requirement of the LEP activity in the MBO42− channels significantly decreases. Within the solid solution, two distinct Pb/Sr–O2 bond distances significantly differ, which gradually decreases with increasing strontium content leading to a more symmetric coordination around strontium. The calculated BVS of Pb2+/Sr2+ exhibits a linear correlation with the Wang–Liebau eccentricity parameter, indicating to an increased bonding ability cation. The vibrational properties are characterized by both Raman and FTIR spectroscopy, complementing the XPRD results. Electronic band gaps of selected (Pb1−xSrx)MnBO4 samples were obtained from diffuse reflectance spectroscopy data. Additionally, the Sr containing samples show higher thermal stability than the Pb containing counterparts.
ns 2 立体化学活性孤电子对（LEPs）的存在会导致特定 p 块阳离子周围的原子环境不对称，从而改变相应体系的晶体化学性质。在此，我们报告了一系列莫来石型化合物，以了解 Sr2+ 在多大程度上取代了 (Pb1-x Sr x )MnBO4 中具有立体化学活性的 Pb2+ 阳离子。固溶体的每个成员都是用传统固态方法合成的。利用 X 射线粉末衍射和里特维尔德细化法对多晶样品进行了表征。用 Sr2+ 替代 Pb2+ 会导致 a 晶格参数收缩，而 b 和 c 方向会有轻微拉长。当 Sr2+ 和 Pb2+ 的离子半径相差 1 pm 时，由于 MBO4 2- 通道中 LEP 活性的空间要求显著降低，细胞体积在末端成员之间收缩了约 4%。在固溶体中，两种不同的 Pb/Sr-O2 键距存在显著差异，随着锶含量的增加，键距逐渐减小，导致锶周围的配位更加对称。计算得出的 Pb2+/Sr2+ BVS 与 Wang-Liebau 偏心参数呈线性相关，表明阳离子的成键能力增强。拉曼光谱和傅立叶变换红外光谱对振动特性进行了表征，补充了 XPRD 的结果。从漫反射光谱数据中获得了选定 (Pb1-x Sr x)MnBO4 样品的电子带隙。此外，含 Sr 的样品比含铅的样品具有更高的热稳定性。
{"title":"Synthesis and characterization of (Pb1−x Sr x )MnBO4: a structural and spectroscopic study","authors":"Carla M. Uribe-Rincón, Mohammad Mangir Murshed, Thorsten M. Gesing","doi":"10.1515/zkri-2023-0056","DOIUrl":"https://doi.org/10.1515/zkri-2023-0056","url":null,"abstract":"The presence of <jats:italic>ns</jats:italic> <jats:sup>2</jats:sup> stereo-chemical active lone electron pairs (LEPs) causes asymmetric atomic environments around a given <jats:italic>p</jats:italic>-block cation, leading to change the crystal chemistry of a respective system. Here we report a series of mullite-type compounds to understand at what extend Sr<jats:sup>2+</jats:sup> replaces the stereochemical active Pb<jats:sup>2+</jats:sup> cation in (Pb<jats:sub>1−<jats:italic>x</jats:italic> </jats:sub>Sr<jats:sub> <jats:italic>x</jats:italic> </jats:sub>)MnBO<jats:sub>4</jats:sub>. Each member of the solid solution has been synthesized by conventional solid-state method. The polycrystalline samples are characterized using X-ray powder diffraction followed by Rietveld refinement. Substitution of Pb<jats:sup>2+</jats:sup> with Sr<jats:sup>2+</jats:sup> leads to contraction of the <jats:italic>a</jats:italic> lattice parameter with slight elongation in the <jats:italic>b</jats:italic> and <jats:italic>c</jats:italic> direction. For a difference of 1 pm of the ionic radius between Sr<jats:sup>2+</jats:sup> and Pb<jats:sup>2+</jats:sup>, the cell volume contracts about 4 % between the end members as the spatial requirement of the LEP activity in the MBO<jats:sub>4</jats:sub> <jats:sup>2−</jats:sup> channels significantly decreases. Within the solid solution, two distinct Pb/Sr–O<jats:sub>2</jats:sub> bond distances significantly differ, which gradually decreases with increasing strontium content leading to a more symmetric coordination around strontium. The calculated BVS of Pb<jats:sup>2+</jats:sup>/Sr<jats:sup>2+</jats:sup> exhibits a linear correlation with the Wang–Liebau eccentricity parameter, indicating to an increased bonding ability cation. The vibrational properties are characterized by both Raman and FTIR spectroscopy, complementing the XPRD results. Electronic band gaps of selected (Pb<jats:sub>1−<jats:italic>x</jats:italic> </jats:sub>Sr<jats:sub> <jats:italic>x</jats:italic> </jats:sub>)MnBO<jats:sub>4</jats:sub> samples were obtained from diffuse reflectance spectroscopy data. Additionally, the Sr containing samples show higher thermal stability than the Pb containing counterparts.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"314 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140047662","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}
Alexandru Turza, Maria O. Miclăuș, Gheorghe Borodi
Methenolone and drostanolone are two popular synthetic anabolic-androgenic agents and dihydrotestosterone derivatives which belong to the steroid family. Two esterified prodrugs of methenolone and drostanolone, in the form of methenolone and drostanolone enanthate, have been described from a structural point of view. The crystal structure of drostanolone enanthate was determined by single crystal X-ray diffraction, while the crystal structure of methenolone enanthate was solved by the powder X-ray diffraction technique. The nature and magnitudes of intermolecular interactions were analysed quantitatively by means of crystal lattice energies and Hirshfeld surfaces.
美替诺龙和屈他雄酮是两种常用的合成同化雄激素制剂，也是属于类固醇家族的二氢睾酮衍生物。从结构的角度描述了美替诺龙和屈他雄酮的两种酯化原药，即美替诺龙和屈他雄酮庚酸酯。庚酸屈他雄酮的晶体结构是通过单晶 X 射线衍射法确定的，而庚酸美替诺龙的晶体结构则是通过粉末 X 射线衍射技术解决的。通过晶格能和 Hirshfeld 表面定量分析了分子间相互作用的性质和程度。
{"title":"Exploring the crystal and molecular structures of methenolone and drostanolone enanthate","authors":"Alexandru Turza, Maria O. Miclăuș, Gheorghe Borodi","doi":"10.1515/zkri-2023-0050","DOIUrl":"https://doi.org/10.1515/zkri-2023-0050","url":null,"abstract":"Methenolone and drostanolone are two popular synthetic anabolic-androgenic agents and dihydrotestosterone derivatives which belong to the steroid family. Two esterified prodrugs of methenolone and drostanolone, in the form of methenolone and drostanolone enanthate, have been described from a structural point of view. The crystal structure of drostanolone enanthate was determined by single crystal X-ray diffraction, while the crystal structure of methenolone enanthate was solved by the powder X-ray diffraction technique. The nature and magnitudes of intermolecular interactions were analysed quantitatively by means of crystal lattice energies and Hirshfeld surfaces.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140009711","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}
Jutta Kösters, Valentin Antoine Chamard, Samir F. Matar, Wilma Pröbsting, Theresa Block, Rainer Pöttgen
Ca3Ru3Zn13 was synthesized from the elements in a tantalum tube in a muffle furnace. The sample was annealed to 1123 K followed by slow cooling to enhance crystal growth. Ca3Ru3Zn13 was characterized through a Guinier powder pattern. The structure was refined from single crystal X-ray diffractometer data: new type, Pbcn, a = 522.92(5), b = 1792.72(14), c = 2789.6(2) pm, wR2 = 0.0590, 3451 F2 values, 177 variables. One can describe the Ca3Ru3Zn13 structure by a stacking of closest packed layers of compositions Ca6Zn10, Ca6Zn12 and Ru6Zn15. The calcium atoms have high coordination numbers: Ca1@Zn13Ru3Ca2, Ca2@Zn15Ru4Ca, Ca3@Zn15Ru4Ca and Ca4@Zn15Ru4Ca. The shortest interatomic distances occur between the ruthenium and zinc atoms (255–273 pm). The Ru1@Zn8, Ru2@Zn10 and Ru3@Zn8 polyhedra condense via common edges to the [Ru3Zn13] substructure which hosts the calcium atoms. The zinc substructure consists of 15 crystallographically independent zinc sites with a broader range of Zn–Zn distances (255–307 pm).
{"title":"Ca3Ru3Zn13 – a zinc-rich intermetallic phase composed of closest-packed layers","authors":"Jutta Kösters, Valentin Antoine Chamard, Samir F. Matar, Wilma Pröbsting, Theresa Block, Rainer Pöttgen","doi":"10.1515/zkri-2023-0044","DOIUrl":"https://doi.org/10.1515/zkri-2023-0044","url":null,"abstract":"Ca<jats:sub>3</jats:sub>Ru<jats:sub>3</jats:sub>Zn<jats:sub>13</jats:sub> was synthesized from the elements in a tantalum tube in a muffle furnace. The sample was annealed to 1123 K followed by slow cooling to enhance crystal growth. Ca<jats:sub>3</jats:sub>Ru<jats:sub>3</jats:sub>Zn<jats:sub>13</jats:sub> was characterized through a Guinier powder pattern. The structure was refined from single crystal X-ray diffractometer data: new type, <jats:italic>Pbcn</jats:italic>, <jats:italic>a</jats:italic> = 522.92(5), <jats:italic>b</jats:italic> = 1792.72(14), <jats:italic>c</jats:italic> = 2789.6(2) pm, <jats:italic>wR</jats:italic>2 = 0.0590, 3451 <jats:italic>F</jats:italic> <jats:sup>2</jats:sup> values, 177 variables. One can describe the Ca<jats:sub>3</jats:sub>Ru<jats:sub>3</jats:sub>Zn<jats:sub>13</jats:sub> structure by a stacking of closest packed layers of compositions Ca<jats:sub>6</jats:sub>Zn<jats:sub>10</jats:sub>, Ca<jats:sub>6</jats:sub>Zn<jats:sub>12</jats:sub> and Ru<jats:sub>6</jats:sub>Zn<jats:sub>15</jats:sub>. The calcium atoms have high coordination numbers: Ca1@Zn<jats:sub>13</jats:sub>Ru<jats:sub>3</jats:sub>Ca<jats:sub>2</jats:sub>, Ca2@Zn<jats:sub>15</jats:sub>Ru<jats:sub>4</jats:sub>Ca, Ca3@Zn<jats:sub>15</jats:sub>Ru<jats:sub>4</jats:sub>Ca and Ca4@Zn<jats:sub>15</jats:sub>Ru<jats:sub>4</jats:sub>Ca. The shortest interatomic distances occur between the ruthenium and zinc atoms (255–273 pm). The Ru1@Zn<jats:sub>8</jats:sub>, Ru2@Zn<jats:sub>10</jats:sub> and Ru3@Zn<jats:sub>8</jats:sub> polyhedra condense via common edges to the [Ru<jats:sub>3</jats:sub>Zn<jats:sub>13</jats:sub>] substructure which hosts the calcium atoms. The zinc substructure consists of 15 crystallographically independent zinc sites with a broader range of Zn–Zn distances (255–307 pm).","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139751067","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}
Borate-phosphates exhibit a wide range of compositional and structural diversity, making them ideal hosts for luminescent materials. In this work, a new borate-phosphate compound CsNa2Dy2(BO3)(PO4)2 has been prepared under high temperature solution growth method. It crystallizes in an orthorhombic space group Cmcm with the following lattice parameters determined by single-crystal X-ray diffraction: a = 6.9709(5), b = 14.9699(11), c = 10.6480(8) Å, z = 4. Its structure contains isolated BO3 planar triangles and PO4 tetrahedra, which are interconnected by Cs+, Na+ and Dy3+ ions. Solid solutions of CsNa2Y2(1−x)Dy2x(BO3)(PO4)2 (x = 0 − 0.08) are prepared and exhibit a yellow emissive luminescence by near-UV excitation due to the 4F9/2 → 6H(13/2, 15/2) transitions of Dy3+. The optimized concentration of Dy3+ is x = 0.01, and if over this critical value, the luminescent intensity will decrease due to concentration quenching. The Commission International de L’Eclairage (CIE) coordinates for CsNa2Y1.98Dy0.02(BO3)(PO4)2 are (x = 0.377, y = 0.404), corresponding to yellow color. The prepared phosphor may serve as a yellow phosphor for NUV-excited LEDs.
{"title":"Synthesis, crystal structure and luminescent properties of a quinary borate-phosphate compound CsNa2Dy2(BO3)(PO4)2","authors":"Kai Liu, Shipeng Yang, Junfeng Tian, Peixin Zhang, Xiaohan Hei, Zhongfeng Jiang","doi":"10.1515/zkri-2023-0052","DOIUrl":"https://doi.org/10.1515/zkri-2023-0052","url":null,"abstract":"Borate-phosphates exhibit a wide range of compositional and structural diversity, making them ideal hosts for luminescent materials. In this work, a new borate-phosphate compound CsNa<jats:sub>2</jats:sub>Dy<jats:sub>2</jats:sub>(BO<jats:sub>3</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>2</jats:sub> has been prepared under high temperature solution growth method. It crystallizes in an orthorhombic space group <jats:italic>Cmcm</jats:italic> with the following lattice parameters determined by single-crystal X-ray diffraction: <jats:italic>a</jats:italic> = 6.9709(5), <jats:italic>b</jats:italic> = 14.9699(11), <jats:italic>c</jats:italic> = 10.6480(8) Å, <jats:italic>z</jats:italic> = 4. Its structure contains isolated BO<jats:sub>3</jats:sub> planar triangles and PO<jats:sub>4</jats:sub> tetrahedra, which are interconnected by Cs<jats:sup>+</jats:sup>, Na<jats:sup>+</jats:sup> and Dy<jats:sup>3+</jats:sup> ions. Solid solutions of CsNa<jats:sub>2</jats:sub>Y<jats:sub>2(1−<jats:italic>x</jats:italic>)</jats:sub>Dy<jats:sub>2<jats:italic>x</jats:italic> </jats:sub>(BO<jats:sub>3</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>2</jats:sub> (<jats:italic>x</jats:italic> = 0 − 0.08) are prepared and exhibit a yellow emissive luminescence by near-UV excitation due to the <jats:sup>4</jats:sup>F<jats:sub>9/2</jats:sub> → <jats:sup>6</jats:sup>H<jats:sub>(13/2, 15/2)</jats:sub> transitions of Dy<jats:sup>3+</jats:sup>. The optimized concentration of Dy<jats:sup>3+</jats:sup> is <jats:italic>x</jats:italic> = 0.01, and if over this critical value, the luminescent intensity will decrease due to concentration quenching. The Commission International de L’Eclairage (CIE) coordinates for CsNa<jats:sub>2</jats:sub>Y<jats:sub>1.98</jats:sub>Dy<jats:sub>0.02</jats:sub>(BO<jats:sub>3</jats:sub>)(PO<jats:sub>4</jats:sub>)<jats:sub>2</jats:sub> are (<jats:italic>x</jats:italic> = 0.377, <jats:italic>y</jats:italic> = 0.404), corresponding to yellow color. The prepared phosphor may serve as a yellow phosphor for NUV-excited LEDs.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139553396","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}
Tobias A. Teichtmeister, Stefan Schwarzmüller, Klaus Wurst, Gunter Heymann, Hubert Huppertz
Tm2CrB3O9 was obtained by high-pressure/high-temperature syntheses at 7.5 GPa and 850 °C. The compound crystallizes homeotypically to walstromite in the triclinic space group P1¯$Pbar{1}$ (no. 2) with the unit cell parameters a = 5.9118(4) Å, b = 5.9148(4) Å, c = 8.3575(6) Å, α = 83.64(1)°, β = 71.19(1)°, and γ = 79.93(1)°, and two formula units per cell. Single-crystal and powder diffraction data are accompanied by an infrared spectroscopic investigation and the structural features of this new compound are discussed in detail.
{"title":"High-pressure/high-temperature synthesis of the first walstromite-analogue borate Tm2CrB3O9","authors":"Tobias A. Teichtmeister, Stefan Schwarzmüller, Klaus Wurst, Gunter Heymann, Hubert Huppertz","doi":"10.1515/zkri-2023-0046","DOIUrl":"https://doi.org/10.1515/zkri-2023-0046","url":null,"abstract":"Tm<jats:sub>2</jats:sub>CrB<jats:sub>3</jats:sub>O<jats:sub>9</jats:sub> was obtained by high-pressure/high-temperature syntheses at 7.5 GPa and 850 °C. The compound crystallizes homeotypically to walstromite in the triclinic space group <jats:inline-formula> <jats:alternatives> <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <m:mi>P</m:mi> <m:mover> <m:mn>1</m:mn> <m:mo>¯</m:mo> </m:mover> </m:math> <jats:tex-math>$Pbar{1}$</jats:tex-math> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/j_zkri-2023-0046_ineq_001.png\" /> </jats:alternatives> </jats:inline-formula> (no. 2) with the unit cell parameters <jats:italic>a</jats:italic> = 5.9118(4) Å, <jats:italic>b</jats:italic> = 5.9148(4) Å, <jats:italic>c</jats:italic> = 8.3575(6) Å, <jats:italic>α</jats:italic> = 83.64(1)°, <jats:italic>β</jats:italic> = 71.19(1)°, and <jats:italic>γ</jats:italic> = 79.93(1)°, and two formula units per cell. Single-crystal and powder diffraction data are accompanied by an infrared spectroscopic investigation and the structural features of this new compound are discussed in detail.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139056531","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}
Abstract The intermetallic ytterbium compound Yb2Pd2Cd shows a structural phase transition at ∼150 K. The structures of the room-temperature (Mo2B2Fe type, P4/mbm, a = 757.07(7), c = 371.99(4) pm, wR2 = 0.0620, 272 F 2 values, 12 variables) and low-temperature (new type, P4/mbm, a = 747.26(4), c = 741.46(4) pm, wR2 = 0.0384, 511 F 2 values, 19 variables) modifications were refined from single crystal X-ray diffractometer data. The superstructure formation corresponds to an isomorphic transition of index 2. The driving force for the structural phase transition is an ytterbium charge ordering (the superstructure exhibits two crystallographically independent ytterbium sites) with a much higher degree of divalent ytterbium in the low-temperature modification. The striking structural feature concerns the ytterbium–palladium coordination with different Yb–Pd distances: longer ones for predominantly divalent Yb1 (2 × 284.7 and 4 × 296.1 pm, ∅ = 292.3 pm) and shorter ones for trivalent Yb2 (2 × 277.5 and 4 × 288.4 pm, ∅ = 284.8 pm).
摘要 金属间镱化合物 Yb2Pd2Cd 在 ∼150 K 时出现了结构相变。根据单晶 X 射线衍射仪数据，完善了室温（Mo2B2Fe 型，P4/mbm，a = 757.07(7), c = 371.99(4) pm，wR2 = 0.0620，272 F 2 值，12 个变量）和低温（新型，P4/mbm，a = 747.26(4), c = 741.46(4) pm，wR2 = 0.0384，511 F 2 值，19 个变量）修饰结构。超结构的形成与指数 2 的同构转变相对应。结构相变的驱动力是镱电荷有序化（超结构显示出两个晶体学上独立的镱位点），低温改性时的二价镱含量更高。结构上的显著特点是镱-钯配位具有不同的镱-钯距离：二价镱1的配位距离较长（2 × 284.7 和 4 × 296.1 pm，∅ = 292.3 pm），而三价镱2的配位距离较短（2 × 277.5 和 4 × 288.4 pm，∅ = 284.8 pm）。
{"title":"Ytterbium valence ordering in the low-temperature superstructure of Yb2Pd2Cd","authors":"Jutta Kösters, Rainer Pöttgen","doi":"10.1515/zkri-2023-0043","DOIUrl":"https://doi.org/10.1515/zkri-2023-0043","url":null,"abstract":"Abstract The intermetallic ytterbium compound Yb2Pd2Cd shows a structural phase transition at ∼150 K. The structures of the room-temperature (Mo2B2Fe type, P4/mbm, a = 757.07(7), c = 371.99(4) pm, wR2 = 0.0620, 272 F 2 values, 12 variables) and low-temperature (new type, P4/mbm, a = 747.26(4), c = 741.46(4) pm, wR2 = 0.0384, 511 F 2 values, 19 variables) modifications were refined from single crystal X-ray diffractometer data. The superstructure formation corresponds to an isomorphic transition of index 2. The driving force for the structural phase transition is an ytterbium charge ordering (the superstructure exhibits two crystallographically independent ytterbium sites) with a much higher degree of divalent ytterbium in the low-temperature modification. The striking structural feature concerns the ytterbium–palladium coordination with different Yb–Pd distances: longer ones for predominantly divalent Yb1 (2 × 284.7 and 4 × 296.1 pm, ∅ = 292.3 pm) and shorter ones for trivalent Yb2 (2 × 277.5 and 4 × 288.4 pm, ∅ = 284.8 pm).","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"43 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138943595","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}
Juan Medina-Jurado, Alex J. Corkett, R. Dronskowski
Abstract Solid-state carbodiimides and cyanamides are a group of compounds that generally shows motifs of layered structures, with an alternating sequence of metal cations and NCN2− anions. A study of the relationship between the ionic sizes in the cation layer and the crystal structures found is presented using the geometric characteristics of the NCN2− coordination environment. The results of this analysis reveal a ‘Goldilocks zone’ of cationic sizes, from Al3+ to Tl+, that are capable of forming stable “layered” metal carbodiimide structures. Furthermore, by employing a vectorial approach a correlation between the size difference of the cations and the degree of tilting of the NCN2− framework has been found, capable of predicting the likelihood of new phases crystallizing in such structures.
{"title":"Finding the ‘Goldilocks Zone’: cationic size and tilting of carbodiimide and cyanamide anions","authors":"Juan Medina-Jurado, Alex J. Corkett, R. Dronskowski","doi":"10.1515/zkri-2023-0049","DOIUrl":"https://doi.org/10.1515/zkri-2023-0049","url":null,"abstract":"Abstract Solid-state carbodiimides and cyanamides are a group of compounds that generally shows motifs of layered structures, with an alternating sequence of metal cations and NCN2− anions. A study of the relationship between the ionic sizes in the cation layer and the crystal structures found is presented using the geometric characteristics of the NCN2− coordination environment. The results of this analysis reveal a ‘Goldilocks zone’ of cationic sizes, from Al3+ to Tl+, that are capable of forming stable “layered” metal carbodiimide structures. Furthermore, by employing a vectorial approach a correlation between the size difference of the cations and the degree of tilting of the NCN2− framework has been found, capable of predicting the likelihood of new phases crystallizing in such structures.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"47 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138943805","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}
Aylin Koldemir, Josef Maximilian Gerdes, Maximilian Kai Reimann, Michael Ryan Hansen, Rainer Pöttgen
The silicides ScT2Si2 (T = Ru, Rh, Os) were synthesized by arc-melting of the elements and subsequent annealing in sealed silica ampoules. They crystallize with the rarely observed HfFe2Si2 type structure, space group Pbcm. The structures of ScRu2Si2 (a = 761.64(4), b = 730.70(6), c = 521.07(6) pm, wR = 0.0314, 633 F2 values, 31 variables) and ScOs2Si2 (a = 771.10(8), b = 736.68(7), c = 521.88(5) pm, wR = 0.0479, 623 F2 values, 31 variables) were refined from single crystal X-ray diffractometer data. The refinements showed small degrees of Ru/Si respectively Os/Si mixing on one 4c site, leading to the refined compositions ScRu1.96(1)Si2.04(1) and ScOs1.91(1)Si2.09(1). The monomeric building units in both structures are two slightly distorted, crystallographically independent RuSi5 respectively OsSi5 square pyramids, which are condensed via common edges. The resulting densely packed [Ru2Si2] and [Os2Si2] networks leave voids for the scandium atoms with coordination number 18: Sc@Si8Ru8Sc2 and Sc@Si8Os8Sc2. Temperature dependent magnetic susceptibility measurements of ScRu2Si2 and ScOs2Si2 indicate Pauli paramagnetism. Solid-state 29Si and 45Sc static and MAS NMR spectroscopy reveal significant Knight shifts and a strong influence of the T/Si mixing on the experimental NMR line shapes. A larger overall 29Si magnetic shift for ScRu2Si2 compared to ScOs2Si2, although with a negative sign for one of the 29Si resonances, suggests stronger paramagnetic effects for ScRu2Si2, in agreement with the magnetic susceptibility measurements.
{"title":"The HfFe2Si2 type silicides ScT 2Si2 (T = Ru, Rh, Os) – structure and solid-state 29Si/45Sc NMR spectroscopy","authors":"Aylin Koldemir, Josef Maximilian Gerdes, Maximilian Kai Reimann, Michael Ryan Hansen, Rainer Pöttgen","doi":"10.1515/zkri-2023-0048","DOIUrl":"https://doi.org/10.1515/zkri-2023-0048","url":null,"abstract":"The silicides Sc<jats:italic>T</jats:italic> <jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> (<jats:italic>T</jats:italic> = Ru, Rh, Os) were synthesized by arc-melting of the elements and subsequent annealing in sealed silica ampoules. They crystallize with the rarely observed HfFe<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> type structure, space group <jats:italic>Pbcm</jats:italic>. The structures of ScRu<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> (<jats:italic>a</jats:italic> = 761.64(4), <jats:italic>b</jats:italic> = 730.70(6), <jats:italic>c</jats:italic> = 521.07(6) pm, w<jats:italic>R</jats:italic> = 0.0314, 633 <jats:italic>F</jats:italic> <jats:sup>2</jats:sup> values, 31 variables) and ScOs<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> (<jats:italic>a</jats:italic> = 771.10(8), <jats:italic>b</jats:italic> = 736.68(7), <jats:italic>c</jats:italic> = 521.88(5) pm, w<jats:italic>R</jats:italic> = 0.0479, 623 <jats:italic>F</jats:italic> <jats:sup>2</jats:sup> values, 31 variables) were refined from single crystal X-ray diffractometer data. The refinements showed small degrees of Ru/Si respectively Os/Si mixing on one 4<jats:italic>c</jats:italic> site, leading to the refined compositions ScRu<jats:sub>1.96(1)</jats:sub>Si<jats:sub>2.04(1)</jats:sub> and ScOs<jats:sub>1.91(1)</jats:sub>Si<jats:sub>2.09(1)</jats:sub>. The monomeric building units in both structures are two slightly distorted, crystallographically independent RuSi<jats:sub>5</jats:sub> respectively OsSi<jats:sub>5</jats:sub> square pyramids, which are condensed via common edges. The resulting densely packed [Ru<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub>] and [Os<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub>] networks leave voids for the scandium atoms with coordination number 18: Sc@Si<jats:sub>8</jats:sub>Ru<jats:sub>8</jats:sub>Sc<jats:sub>2</jats:sub> and Sc@Si<jats:sub>8</jats:sub>Os<jats:sub>8</jats:sub>Sc<jats:sub>2</jats:sub>. Temperature dependent magnetic susceptibility measurements of ScRu<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> and ScOs<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> indicate Pauli paramagnetism. Solid-state <jats:sup>29</jats:sup>Si and <jats:sup>45</jats:sup>Sc static and MAS NMR spectroscopy reveal significant Knight shifts and a strong influence of the <jats:italic>T</jats:italic>/Si mixing on the experimental NMR line shapes. A larger overall <jats:sup>29</jats:sup>Si magnetic shift for ScRu<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub> compared to ScOs<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub>, although with a negative sign for one of the <jats:sup>29</jats:sup>Si resonances, suggests stronger paramagnetic effects for ScRu<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub>, in agreement with the magnetic susceptibility measurements.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138824573","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}
A survey of the crystallographically determined structures of the Group 13 dithiophosphates and dithiophosphinates is presented with a focus upon both the molecular structures and supramolecular association involving the heavy element. Only small numbers of aluminium(III) (two) and gallium(III) (one) structures are known and these along with the 10 indium(III) examples have a preponderance towards homoleptic species with most coordination geometries based on an octahedron owing to the presence of symmetrically or almost symmetrically chelating phosphorodithiolato ligands; the notable exception is the gallium species which has an approximately tetrahedral geometry as two of the dithiophosphinate ligands coordinate in a monodentate mode. Diverse molecular structures are noted for the four heteroleptic examples of the lighter Group 13 elements which assemble in their crystals employing intermolecular interactions that do not involve the central element, as with the homoleptic structures. A completely different situation is evident for the thallium(I)/(III) structures which display a diverse array of coordination geometries and which usually assemble via Tl⋯S triel-bonding interactions; in the supramolecular assembly of thallium(I) crystals, Tl(lone-pair)⋯π(aryl) interactions are often observed.
{"title":"A bibliographic survey of the structural chemistry of the Group 13 dithiophosphates and dithiophosphinates","authors":"Edward R. T. Tiekink","doi":"10.1515/zkri-2023-0045","DOIUrl":"https://doi.org/10.1515/zkri-2023-0045","url":null,"abstract":"A survey of the crystallographically determined structures of the Group 13 dithiophosphates and dithiophosphinates is presented with a focus upon both the molecular structures and supramolecular association involving the heavy element. Only small numbers of aluminium(III) (two) and gallium(III) (one) structures are known and these along with the 10 indium(III) examples have a preponderance towards homoleptic species with most coordination geometries based on an octahedron owing to the presence of symmetrically or almost symmetrically chelating phosphorodithiolato ligands; the notable exception is the gallium species which has an approximately tetrahedral geometry as two of the dithiophosphinate ligands coordinate in a monodentate mode. Diverse molecular structures are noted for the four heteroleptic examples of the lighter Group 13 elements which assemble in their crystals employing intermolecular interactions that do not involve the central element, as with the homoleptic structures. A completely different situation is evident for the thallium(I)/(III) structures which display a diverse array of coordination geometries and which usually assemble via Tl⋯S triel-bonding interactions; in the supramolecular assembly of thallium(I) crystals, Tl(lone-pair)⋯π(aryl) interactions are often observed.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138579495","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}
Maria A. Brusina, Vladislav V. Gurzhiy, Leonid V. Myznikov, Viktor V. Iljin, Stanislav M. Ramsh, Levon B. Piotrovskiy
Crystal structure of a series of 1-alkylimidazole-4,5-dicarboxylic acids has been determined. It is shown that an increase in the length of the alkyl group leads to drastic changes in the crystal and molecular structures. 1-Methyl and 1-ethylimidazole-4,5-dicarboxylic acid crystallize in zwitterionic form, but 1-propyl- and 1-butylimidazole-4,5-dicarboxylic acid crystallize as rare equimolar mixture of neutral and zwitterionic tautomeric forms. The observed changes in the crystal and molecular structures are apparently associated with the steric factor, which determines both the packing method and the tautomeric composition of the unit cell.
{"title":"Crystal structures of а series of 1-substituted imidazol-4,5-dicarboxylic acids","authors":"Maria A. Brusina, Vladislav V. Gurzhiy, Leonid V. Myznikov, Viktor V. Iljin, Stanislav M. Ramsh, Levon B. Piotrovskiy","doi":"10.1515/zkri-2023-0022","DOIUrl":"https://doi.org/10.1515/zkri-2023-0022","url":null,"abstract":"Crystal structure of a series of 1-alkylimidazole-4,5-dicarboxylic acids has been determined. It is shown that an increase in the length of the alkyl group leads to drastic changes in the crystal and molecular structures. 1-Methyl and 1-ethylimidazole-4,5-dicarboxylic acid crystallize in zwitterionic form, but 1-propyl- and 1-butylimidazole-4,5-dicarboxylic acid crystallize as rare equimolar mixture of neutral and zwitterionic tautomeric forms. The observed changes in the crystal and molecular structures are apparently associated with the steric factor, which determines both the packing method and the tautomeric composition of the unit cell.","PeriodicalId":23855,"journal":{"name":"Zeitschrift für Kristallographie - Crystalline Materials","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138542061","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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