bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular dynamics simulations reveal structural coordination of Ffh‐FtsY heterodimer toward GTPase activation
Authors: Yang Ming‐Jun , Zhang Xin 
Published: January 2011

AbstractTwo homologous GTPases (guanine‐triphosphatases) in the signal recognition particle (SRP) and its receptor (SR) use their cumulative energy during GTP (guanine‐triphosphate) hydrolysis to control the co‐translational protein targeting process. Distinct from classical GTPases, which rely on external factors to hydrolyze GTP, SRP GTPases stimulate one another's activity in a self‐sufficient manner upon SRP–SR complex association. Although both ground‐state and putative transition‐state GTP analogs have been used to recapitulate the state of GTPase activation, the underlying mechanism of the activated state still remains elusive. In particular, several residues that were placed in pending positions have been shown to be important to GTP hydrolysis in biochemical studies. Here, we examined the stability and dynamics of three interaction networks involving these residues and discovered that they contribute to the GTPase activation via well‐tuned conformational changes. The crystallographically identified pending residues Ffh:R191/FtsY:R195 undergo extensive conformational rearrangements to form persisted interactions with FtsY:E284/Ffh:E274, explaining the biochemically observed defective effect of R191 mutant to the activation of both GTPases. In addition, the side chain of FtsY:R142, one of the most important catalytic residues, rotates to an extended conformation that could more efficiently maintain the electrostatic balance for GTP hydrolysis. Finally, the invariant residues Ffh:G190 and FtsY:G194, instead of the supposed auxiliary water molecules, are proposed to stabilize the nucleophilic waters during GTPase activation. In complementary to experimental observations, these findings suggest a more favorable interaction model for SRP GTPase activation and would thus benefit to our understanding of how SRP GTPases regulate the protein targeting pathway. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Predictive skill of a subset of models participating in D‐PHASE in the COPS region
Authors: Bauer Hans‐Stefan , Weusthoff Tanja , Dorninger Manfred , Wulfmeyer Volker , Schwitalla Thomas , Gorgas Theresa , Arpagaus Marco , Warrach‐Sagi Kirsten 
Published: January 2011

AbstractThe unique combination of observing and modelling efforts during the Convective and Orographically‐induced Precipitation Study (COPS) and D‐PHASE (Demonstration of the Probabilistic Hydrological and Atmospheric Simulation of flood Events in the alpine region) allows the systematic evaluation of models participating in D‐PHASE with observations collected during COPS. This study verifies a subset of the D‐PHASE models in the COPS region, including convection‐permitting models as well as models with convection parametrization. Observations from the Joint D‐PHASE/COPS (JDC) dataset are applied and processed with the Vienna Enhanced Resolution Analysis (VERA). The focus is set on monthly accumulated sums of the 12‐hourly precipitation between 0600 and 1800 UTC and includes comparisons of horizontal distributions, averaged diurnal cycles and neighbourhood verification techniques. Two fuzzy verification scores were applied: The Fractions Skill Score (FSS) and Upscaling.The FSS analysis shows that all models are capable of forecasting the correct distribution of precipitation, especially for low precipitation thresholds. Low scores in the upscaling analysis reveal weaknesses in predicting the amounts of precipitation. The high‐resolution models usually outperform their lower‐resolution counterparts. This is true for the skill score analysis as well as the comparison of the horizontal distribution and the diurnal cycle averaged over the COPS period. Large differences between the models and the observations occur in regions with complex terrain, especially for models applying a convection scheme. Copyright © 2011 Royal Meteorological Society
Long‐range transport of Saharan dust and its radiative impact on precipitation forecast: a case study during the Convective and Orographically‐induced Precipitation Study (COPS)
Authors: Chaboureau Jean‐Pierre , Richard Evelyne , Pinty Jean‐Pierre , Flamant Cyrille , Di Girolamo Paolo , Kiemle Christoph , Behrendt Andreas , Chepfer Hélène , Chiriaco Marjolaine , Wulfmeyer Volker 
Published: January 2011

AbstractA Saharan dust event affected the Rhine valley in southwestern Germany and eastern France on 1 August 2007 during the Convective and Orographically‐induced Precipitation Study (COPS) experiment. Prior to an episode of intense convection, a layer of dry, clean air capped by a moist, dusty layer was observed using Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and airborne and ground‐based lidar observations from North Africa to western Europe. The origin of the different layers was investigated using the regional model Meso‐NH. For the purpose of modelling evaluation, a lidar simulator was developed for direct comparison of observed and simulated vertical structures of the lidar backscattered signal. Overall, the model reproduced the vertical structure of dust probed several times by the different lidar systems during its long‐range transport. From Lagrangian back trajectories it was found that the dust was mobilized from sources in Mauritania six days earlier, while the dry layer subsided over the north Atlantic. Off the Moroccan coasts, the dry layer folded down beneath the dusty air mass and the two‐layer structure was advected to the Rhine valley in about two days. By heating the atmosphere, the dust layer changed the static stability of the atmosphere and thus the occurrence of convection. A study of sensitivity to the radiative effect of dust showed a better prediction of precipitation when a dust prognostic scheme was used rather than climatology or when dust effects were ignored. This result suggests that dust episodes that occur prior to convective events might be important for quantitative precipitation forecasts. Copyright © 2011 Royal Meteorological Society
Prediction of delivery mode with transperineal ultrasound in women with prolonged first stage of labor
Authors: Torkildsen E. A. , Salvesen K. Å. , Eggebø T. M. 
Published: January 2011

AbstractObjectiveTo investigate if fetal head–perineum distance and angle of progression measured with two‐dimensional (2D) and three‐dimensional (3D) transperineal ultrasound could predict outcome of labor in primiparous women with prolonged first stage of labor.MethodsThis was a prospective observational study of 110 primiparous women with singleton cephalic presentation at term diagnosed with prolonged first stage of labor. Digital assessment of fetal station was related to the ischial spine. Fetal head descent was measured with transperineal ultrasound as the shortest distance from the fetal head to the perineum, and the angle between the pubic symphysis and the fetal head. Receiver–operating characteristics (ROC) curves were constructed and 2D and 3D data acquisitions were compared. The stored 3D volumes were assessed by an examiner blinded to all other data. Vaginal delivery vs. Cesarean section was the primary outcome.ResultsCesarean section was performed in 25% of the women. Areas under the ROC curves for prediction of vaginal delivery were 81% (95% confidence interval (CI), 71–91%) (P < 0.01) and 76% (95% CI, 66–87%) (P < 0.01) for fetal head–perineum distance and angle of progression, respectively, as measured by 2D ultrasound and 66% (95% CI, 54–79%) for digital assessment of fetal station (P = 0.01). In 50% of women fetal head–perineum distance was ⩽ 40 mm and 93% (95% CI, 83–97%) of them delivered vaginally vs. 18% (95% CI, 5–48%) with distance > 50 mm. In 48% of women the angle of progression was ≥ 110° and 87% (95% CI, 75–93%) of them delivered vaginally vs. 38% (95% CI, 21–57%) with angle < 100°. Results from 2D and 3D acquisitions were similar.ConclusionFetal head–perineum distance and angle of progression measured with 2D or 3D ultrasound can predict labor outcome, with similar predictive values for the two techniques. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
The thymic–thoracic ratio in fetal heart defects: a simple way to identify fetuses at high risk for microdeletion 22q11
Authors: Chaoui R. , Heling K.‐S. , Sarut Lopez A. , Thiel G. , Karl K. 
Published: January 2011

AbstractObjectivesTo establish reference ranges for the fetal thymic–thoracic ratio (TT‐ratio) and to compare results with those from fetuses with congenital heart defects (CHD) with and without microdeletion 22q11 (del.22q11), a condition known to be associated with a hypoplastic thymus.MethodsTT‐ratio was defined as the quotient of the anteroposterior thymic to the intrathoracic mediastinal diameters measured in the three vessels and trachea view. This ratio was measured in a prospective cross‐sectional study of 302 normal healthy fetuses between 15 and 39 weeks' gestation. The study group comprised two groups: one group (CHDn) consisted of 90 fetuses with CHD and a normal karyotype with no del.22q11 and the other group (CHD22) included 20 fetuses with CHD and a normal karyotype but with proven del.22q11.ResultsThe TT‐ratio of the normal fetuses did not show any statistically significant change during gestation, with a mean value of 0.44. The values of all 90 fetuses of the CHDn group were within the normal range and no different from normal fetuses. However, 19 of the 20 (95%) fetuses in the CHD22 group had a significantly smaller TT‐ratio (P < 0.001) compared with both the CHDn group and the normal fetuses, having a mean value of 0.25.ConclusionsThe TT‐ratio is reliable and easy to obtain during fetal echocardiography. Fetuses with CHD and a low TT‐ratio can be considered at high risk of having microdeletion del.22q11. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Robustness
Authors: Morgenthaler Stephan 
Published: January 2011

AbstractThat the conclusion based on a data analysis be robust and stable is not merely a desirable feature, it is essential. To merit this quality label, a conclusion must be supported by strong data‐based evidence and not simply be a discovery gleaned from a preconceived model and weakly supported by a part of the data. Robustness in statistics refers to the definition and investigation of procedures that lead to such stability. This article gives a brief overview of the concepts and procedures that are relevant in judging robustness. These have mostly been developed over the last five decades. WIREs Comp Stat 2011 3 85–94 DOI: 10.1002/wics.144This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Exploratory Data Analysis
Statistical and Graphical Methods of Data Analysis > Nonparametric Methods
Statistical and Graphical Methods of Data Analysis > Robust Methods
Magnetoliposomes as magnetic resonance imaging contrast agents
Authors: Soenen Stefaan J. , Velde Greetje Vande , Ketkar‐Atre Ashwini , Himmelreich Uwe , De Cuyper Marcel 
Published: January 2011

AbstractAmong the wide variety in iron oxide nanoparticles which are routinely used as magnetic resonance imaging (MRI) contrast agents, magnetoliposomes (MLs) take up a special place. In the present work, the two main types (large and small MLs) are defined and their specific features are commented. For both types of MLs, the flexibility of the lipid coating allows for efficient functionalization, enabling bimodal imaging (e.g., MRI and fluorescence) or the use of MLs as theranostics. These features are especially true for large MLs, where several magnetite cores are encapsulated within a single large liposome, which were found to be highly efficient theranostic agents. By carefully fine‐tuning the number of magnetite cores and attaching Gd3+‐complexes onto the liposomal surface, the large MLs can be efficiently optimized for dynamic MRI. A special type of MLs, biogenic MLs, can also be efficiently used in this regard, with potential applications in cancer treatment and imaging. Small MLs, where the lipid bilayer is immediately attached onto a solid magnetite core, give a very high r2/r1 ratio. The flexibility of the lipid bilayer allows the incorporation of poly(ethylene glycol)–lipid conjugates to increase blood circulation times and be used as bone marrow contrast agents. Cationic lipids can also be incorporated, leading to high cell uptake and associated strong contrast generation in MRI of implanted cells. Unique for these small MLs is the high resistance the particles exhibit against intracellular degradation compared with dextran‐ or citrate‐coated particles. Additionally, intracellular clustering of the iron oxide cores enhances negative contrast generation and enables longer tracking of labeled cells in time. WIREs Nanomed Nanobiotechnol 2011 3 197–211 DOI: 10.1002/wnan.122This article is categorized under:

Diagnostic Tools > Diagnostic Nanodevices
Diagnostic Tools > In Vivo Nanodiagnostics and Imaging
Synthese und Kristallstruktur von (Ph3PNPPh3)2[Cu(N3)4]
Authors: Hiller W. , Hösler K. , Dehnicke K. 
Published: January 2011

AbstractInhaltsübersicht. Die Titelverbindung entsteht neben CuN3 · PPh3 bei der Einwirkung von Natriumazid auf CuCl2 und Triphenylphosphan in siedendem Acetonitril bei Anwesenheit von 15‐Krone‐5 als Lösungsvermittler für NaN3. (Ph3PNPPh3)2[Cu(N3)4] bildet schwarze Kristalle, die wir durch das IR‐Spektrum und durch eine röntgenographische Strukturanalyse charakterisiert haben. Raumgruppe Pbca, Z = 4, (4245 beobachtete unabhängige Reflexe, R = 7,2%), Gitter‐abmessungen (20°C):a = 1980, 1;b = 1618,8; c = 2014,3 pm. Die Verbindung besteht aus Kationen [Ph3PNPPh3]+ und Anionen [Cu(N3)4]2– der Symmetrie Ci, in denen das Cu‐Atom planar von den α‐N‐Atomen der Azidgruppen mit Cu–N‐Abständen von 197,2(4) und 189,5(4) pm umgeben ist.Synthesis and Crystal Structure of (Ph3PNPPh3)2[Cu(N3)4]The title compound is prepared besides CuN3 · PPh3 by the reaction of sodium azide with CuCl2 and PPh3 in boiling acetonitrile in the presence of 15‐crown‐5. (Ph3PNPPh3)2[Cu(N3)4] forms black crystals, which have been characterized by their IR spectrum as well as by an X‐ray structure determination. Space group Pbca, Z = 4 (4245 observed independent reflexions, R = 0.072), lattice dimensions (20°C): A = 1980.1; b = 1618.8; c = 2014.3 pm. The compound consists of Ph3PNPPh3+ cations and anions [Cu(N3)4]2– with symmetry C1, in which the copper atom is planarly surrounded by the four nitrogen atoms of the azide groups with bond lengths Cu–N of 197.2(4) and 189.5(4) pm, respectively.
Chemie polyfunktioneller Moleküle. 103 [1]: Chrom‐, Molybdän‐ und Wolframtetra‐ sowie ‐tricarbonyl‐Komplexe eines Diphenylphosphin‐substituierten Cyclophosphamide
Authors: Eikermann J. , Moll M. , Will N. 
Published: January 2011

AbstractInhaltsübersicht. (Ph2PCH2CH2)2N‐P(O)N(H)CH2CH2CH2O (2) bildet mit cis‐M(CO)4(C7H8) bzw. fac‐M(CO)3(CH3CN)3 (M = Cr, Mo, W; C7H8 = Norbornadien) die Chelat‐komplexe cis‐M(CO)4(PPh2CH2CH2)2N‐P(O)N(H)CH2CH2CH2O (3a–c) bzw. fac‐M(CO)3(PPh2CH2CH2)2N–P(O)N(H)CH2CH2CH2O (4a–c). 3a kristallisiert mit einem Mol Methanol aus, während 4a–c jeweils ein halbes Mol THF als Solvat enthalten. Alle Verbindungen wurden, soweit möglich, durch IR‐, Raman‐, 1H‐NMR‐, 31P‐NMR‐, 13C‐NMR‐ und Massenspektren charakterisiert.Chemistry of Polyfunctional Molecules. 103. Chromium, Molybdenum, and Tungsten Tetra‐ and Tricarbonyl Complexes of a Diphenylphosphine‐substituted Cyclophosphamide Abstract. (Ph2PCH2CH2)2N–P(O)N(H)CH2CH2CH2O (2) forms with cis‐M(CO)4(C7H8) or fac‐M(CO)3(CH3CN)3 (M = Cr, Mo, W; C7H8 = norbornadiene) the chelate complexes cis‐M(CO)4(PPh2CH2CH2)2N–P(O)N(H)CH2CH2CH3O (3a–c) or fac‐M(CO)3(PPh2CH2CH2)2N–P(O)N(H)CH2CH2CH2O (4a–c). 3a crystallizes with one mole of methanol whereas 4a–c contain 1/2 mole of THP as solvate. All compounds were, as far as possible, characterized by their IR, Raman, 1H NMR, 31P NMR, 13C NMR, and mass spectra.
Das erste quinquinäre Oxoaurat(I) K6Na[IO6][AuO]2 = K6[NaIO6][AuO2/2]2 [1]
Authors: Schneider J. , Hoppe R. 
Published: January 2011

AbstractInhaltsübersicht. Bei Versuchen zur Darstellung unbekannter Phasen im System A/Au/I/O (mit A = Alkalimetall) entstanden durch Erhitzen eines Gemenges (2,2 K2O + 1,0 NaIO4; Au‐Rohr; 700°C, 59 d) farblose, transparente Einkristalle von K6NaAu2IO8, das nach Einkristalldaten (Vierkreisdiffraktometerdaten, 2465 Io(hkl), AgKα, R = 6,8% und Rw = 5,6%) monoklin in P2/c mit a = 707,4 pm; b = 977,3 pm; c = 1199,4 pm; β = 122,9°; Z = 2 kristallisiert. Charakteristisch sind die hier erstmals gefundenen, HgO‐analogen Zickzackketten [AuO2/2] längs [001]. Daneben prägen, den NaIO6‐Teil der Struktur betreffend, Ketten aus [IO6]‐Oktaeder, über Na in prismatischer Koordination verknüpft, den Aufbau.The First Quinquinary Oxoaurate(I). K6Na[IO6][AuO]2 = K6[NaIO6][AuO2/2]2Attempting to synthesize unknown phases in the system A/Au/I/O by heating a mixture of K2O and NaIO4 (K: Na = 2.2:1.0, sealed gold tube, 700°C) we obtained colourless, transparent single crystals of K6NaAu2IO6, a new type of Oxoaurate(I). According to single crystal data K6NaAu2IO8 crystallizes in a monoclinic form with a = 707.4 pm, b = 977.3 pm, c = 1199.4 pm β = 122.9° (Z = 2, space group P2/c). Essential part of the structure are chains NaIO6 and zigzag chains AuO2/2, both along [001]. The Madelung part of the lattice energy, MAPLE, and effective coordination numbers, ECoN, are calculated and discussed.
Neue Vertreter des K2Li14[Pb3O14]‐Typs Cs2Li14[Tb3O14] und K2Li14[Zr3O14] [1, 2]
Authors: Voigt S. , Werthmann R. , Hoppe R. 
Published: January 2011

AbstractInhaltsübersicht. Erstmals wurden klar durchscheinende, orange‐farbene Einkristalle von Cs2Li14[Tb3O14] aus Cs2TbO3 und Li2O (Tb: Li = 1:5) dargestellt [550°C, 21 d, verschlossenes AuRohr]. Es liegt der K2Li14[Pb3O14]‐Typ vor [Vierkreisdiffraktometerdaten, PW 1100, MoKä‐Strahlung, 660 Io(hkl), R = 4,8%, Rw = 3,4%, Immm, a = 1293,5(8), b = 792,6(3), c = 740,4(3) pm, Z = 2, drö = 4,65].Ebenfalls neu wurde K2Li14[Zr3O14] in Form farbloser Einkristalle durch Tempern inniger Gemenge von K2O, Li2O und ZrO2 (K: Li: Zr = 1:4:1,5) dargestellt [900°C, 14 d, geschlossene Ni‐Bombe] und röntgenographisch untersucht. Die Strukturverfeinerung [612 Io(hkl), Vierkreisdiffraktometerdaten, PW 1100, MoKα‐Strahlung, R = 5,9%, Rw = 5,3%, Immm, a = 1244,6, b = 776,4, c = 724,3 pm, Z = 2] bestätigt die Isotypie mit K2Li14[Pb3O14]. Der Madelunganteil der Gitterenergie, MAPLE, Effektive Koordinationszahlen, ECoN, diese über Mittlere Effektive Ionenradien, MEFIR, wurden berechnet. Für die nun bekannten Vertreter dieses Typs wurde ein Isotypievergleich vorgenommen.New Compounds of the K2Li14[Pb3O14] Type: Cs2Li14[Tb8O14] and K2Li14[Zr3O14]For the first time Cs2Li14[Tb3O14] has been prepared as orange single crystals from Cs2TbO3 and Li2O (Tb: Li = 1:5) [550°C, 21 d, sealed Au‐Tube]. Structure Refinement [four‐circle diffractometer data, PW 1100, MoKα radiation, 660 Io(hkl), R = 4.8%, Rw = 3.4%, Immm, a = 1293.5(8), b = 792.6(3), c = 740.4(3) pm, Z = 2, drö = 4.65] confirms isotypy with K2Li14[Pb3O14].K2Li14[Zr3O14] has also been prepared as colorless single crystals from K2O, Li2O, and ZrO2 (K: Li: Zr = 1:4:1.5), [900°C, 14 d, closed Ni‐cylinder] and investigated by x‐ray [612 Io(hkl), four‐circle diffractometer data, PW 1100, MoKα radiation, R = 5.9%, Rw = 5.3%, Immm, a = 1244.6, b = 776.4, c = 724.3 pm, Z = 2].The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, are calculated.A detailed comparison of the structures is carried out.
Oxocuprate(I) mit CO2‐analogem Anion: Rb3[CuO2] [1]; (3. Mitteilung)
Authors: Carl W. , Hoppe R. 
Published: January 2011

AbstractInhaltsübersicht. Rb3[CuO2] wurde als dunkelgelbes Pulver bzw. erstmals in Form transparenter gelber, blockförmiger Einkristalle durch Tempern der binären Oxide (RbO0,63/Cu2O, Rb: Cu = 3,1:1 [Pulver] bzw. 4,2:1 [Einkristalle]) hergestellt (geschlossene Cu‐Bömbchen, 600°C/10 d, bzw. 560°C/14 d, dann langsam abgekühlt). Nach Strukturaufklärung (a = 930,9(1); b = 966,8(2); c = 675,5(1) pm, β = 110,1(1)°, P21/n–C52h, Z = 4, Vierkreisdiffraktometer AED2, MoKα, 1409 von 1573 Io(hkl), R = 14,6%, Rw = 10,0%) liegt ein neuer Strukturtyp vor (Parameter siehe Text). Strukturcharakteristisch sind die CO2‐analogen Hanteln [O–Cu–O] mit d(Cu–O) = 177 pm.Die Struktur wird beschrieben. Der Madelunganteil der Gitterenergie, MAPLE, effektive Koordinationszahlen, ECoN, diese über mittlere fiktive Ionenradien, MEFIR, werden berechnet und diskutiert.Oxocuprates(I) with CO2‐analogues Anions: Rb3[CuO2] (3rd Communication)For the first time Rb3[CuO2] was prepared as dark yellow powder resp. yellow single crystals from the binary oxides (RbO0.63/Cu2O, Rb: Cu = 3.1:1 [powder] resp. 4.2:1 [single crystals], sealed Cu‐cylinders). The crystal structure (a = 930.9(1); b = 966.8(2); c = 675.5(1) pm, β = 110.1(1)°, P21/n–C52h, Z = 4, four circle diffractometer AED2, 1409 out of 1573 Io(hkl), R = 14.6%, Rw = 10.0%) was solved. The characteristic element is the CO2‐analogues group [O–Cu–O] with d(Cu–O) = 177 pm. The structure is described. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.
Structure of Cardocyclic Silazaoxanes
Authors: Igonin V. A. , Shklover V. E. , Struchkov YtJ. T. , Zachernyuk A. B. , Isayev V. B. 
Published: January 2011

AbstractAn X‐ray structural study of three new cardocyclic silazaoxanes has been carried out. Central three‐ and tetrasilazane cycles are characterized by stationary values of Si–N bond lengths (1.68–1.72 Å) and Si–NH–Si bond angles (129.5–132.6°); the latter are decreased to 121.2° only in one of the structures. Conformations of the silazane cycles differ significantly even in two independent molecules within one crystal structure. Peripheral trisiloxane cycles are similarly characterized by constancy of Si–O bond lengths (1.62–1.64 Å) and Si–O–Si bond angles (131.4–132.7°), which decrease (down to 1.613 Å) and increase (up to 149.5°) respectively in going to tetrasiloxane cycles.Struktur von Cardocyclischen SilazaoxanenInhaltsübersicht. Eine Röntgenstrukturuntersuchung von drei neuen cardocyclischen Silazaoxanen ist durchgeführt worden. Die zentralen Drei‐ und Tetrasilazan‐Ringe sind durch konstante Werte für die Si–N‐Bindungslängen (1,68–1,72 Å) und Si–NH–Si‐Bindungswinkel (129,5 bis 132,6°) gekennzeichnet; letztere sinken nur in einer Struktur auf 121,2°. Die Konformationen der Silazan‐Ringe unterscheiden sich deutlich, sogar bei zwei unabhängigen Molekülen in einer Kristallstruktur. Die äußeren Trisiloxan‐Ringe sind ebenfalls durch konstante Bindungslängen Si–O (1,62–1,64 Å) und Bindungswinkel Si–O–Si (131,4–132,7°) gekennzeichnet, die bei den Tetrasiloxan‐Ringen auf 1,613 Å sinken bzw. auf 149,5° steigen.