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Artigo Acesso aberto Revisado por pares

Bernt Krebs, Gerald Henkel, M. DARTMANN, W. Preetz, Michael Bruns,

On heating of [(C 2 H 5 ) 4 N][OsCl 6 ] for a short time at 240 °C , Cl 2 is lost and [(C 2 H 5 ) 4 N] 2 [Os 2 Cl 10 ] is formed quantitatively. Both complexes are connected by a temperature dependent redox equilibrium so that by treatment at 120 °C with Cl 2 gas the hexachloroosmate(V) is recovered from the decachlorodiosmate(IV). The crystal structures of salts of both an ions were determined from single crystal X -ray diffraction analyses. [(C 2 H 5 ) 4 N][OsCl 6 ] is monoclinic, space group P2 1 with a = 7 .020 (1), b = ...

Tópico(s): Crystallography and molecular interactions

1984 - De Gruyter | Zeitschrift für Naturforschung B

Artigo Acesso aberto Revisado por pares

W. Preetz, Michael Bruns,

Abstract (TEA)[O S Cl 6 ] is formed quantitatively by heating solid trans-(TEA)[OsX 4 (CO) 2 ] (X = Br, I) in a stream of chlorine at 120 °C, and can be purified by recrystallisation from CH 2 Cl 2 without decomposition. It is reduced immediately by acetone, methanol, Cl - , Br - , I - to give [OsCl 6 ] 2- . The standard potential [OsCl 6 ]-/[OsCl 6 ] 2- in acetonitrile referred to the saturated mercury-mercurous sulphate electrode is 0.840 V. The IR and Ra bands of (TEA)[OsCl 6 ], assigned according to point group Oh, are shifted ...

Tópico(s): Organometallic Compounds Synthesis and Characterization

1983 - De Gruyter | Zeitschrift für Naturforschung B

Artigo Revisado por pares

Joseph Moran, A. Preetz, Ryan Mesch, Michael J. Krische,

Tópico(s): Nanomaterials for catalytic reactions

2011 - Nature Portfolio | Nature Chemistry

Artigo Acesso aberto Revisado por pares

W. Preetz, Michael K. Manthey,

The IR and Raman spectra of the ten bromo-iodo-osmates(IV) [OsBr n I 6-n ] 2- , n = 0-6, including the geometrical isomers for n = 2, 3, 4, have been recorded at low temperature. The vibrational spectra are completely assigned according to point groups O h , D 4h , C 4v , C 3v , and C 2v , as supported by normal coordinate analyses based on a general valence force field. Due to the different trans-influences Br<I in asymmetric axes Br′–Os–I′, the Os–I′ bonds are strengthened and the Os–Br′ bonds are weakened, ...

Tópico(s): Luminescence Properties of Advanced Materials

1992 - De Gruyter | Zeitschrift für Naturforschung B

Artigo Acesso aberto Revisado por pares

Richard Preetz, Andreas Filser, Ana Brömmelhaus, Tim Baalmann, Michael Feldhaus,

The COVID-19 pandemic has disrupted emerging adults’ daily routines due to social distancing, stay-at-home orders, and public and educational facilities’ closure. This article uses longitudinal panel data from Germany ( N = 625) to explore how the COVID-19 pandemic affects emerging adults’ mental health and life satisfaction. Specifically, we investigate risk and protective factors for within-person changes in life satisfaction and mental health using change score models. Our analysis reveals three ...

Tópico(s): Health disparities and outcomes

2021 - SAGE Publishing | Emerging Adulthood

Artigo Revisado por pares

Michael Bruns, W. Preetz,

Abstract Die IR‐ und Ramanspektren der kantenverknüpften Dioktaederanionen [Os 2 X 10 ] 2− , X  Cl, Br, werden entsprechend der Punktgruppe D 2h zugeordnet. Die Banden treten in drei charakteristischen Frequenzbereichen auf; bei hohen Wellenzahlen die Valenzschwingungen mit terminalen Liganden v (OsCl t ): 365–280, v (OsBr t ): 235–195; im mittleren Bereich mit verbrückenden Liganden v (OsCl b ): 270–240, v (OsBr b ); 175–165 cm −1 ; die Deformationsschwingungen liegen bei deutlich niedrigeren Frequenzen. In den Elektronenspektren ...

Tópico(s): Organometallic Compounds Synthesis and Characterization

1986 - Wiley | Zeitschrift für anorganische und allgemeine Chemie

Artigo Revisado por pares

Hans‐Joachim Drexler, Wolfgang Baumann, Thomas Schmidt, Songlin Zhang, Ailing Sun, Anke Spannenberg, Christine Fischer, Helmut Buschmann, Detlef Heller,

... Zhang, A. Sun, A. Spannenberg, A. Arrieta, A. Preetz, D. Heller, Tetrahedron: Asymmetry 2004, 15, 2139–2150. 10.1016/j.tetasy.2004.06.036 CASWeb of Science®Google Scholar 7D. Evans, F. E. Michael, J. S. Tedrow, K. R. Campos, J. Am. ...

Tópico(s): Asymmetric Hydrogenation and Catalysis

2004 - Wiley | Angewandte Chemie International Edition

Artigo Acesso aberto Revisado por pares

Michael K. Manthey, W. Preetz,

All components of the two series [Os 35 Cl n I 6-n ] 2- and [Os 37 Cl n I 6-n ] 2- , n = 0-6, including the pairs of geometric isomers for n = 2, 3, 4, have been prepared and isolated by ion exchange chromatography on DEAE cellulose. The highly resolved low temperature (80 K) IR and Raman spectra of the pure isotopomers show distinct isotopic shifts for different vibrational modes up to 10 cm -1 . Normal coordinate analyses have been performed, based on a general valence force field. Due to the stronger trans influence ...

Tópico(s): Analytical chemistry methods development

1993 - De Gruyter | Zeitschrift für Naturforschung B

Artigo Acesso aberto Revisado por pares

Michael Bruns, W. Preetz,

The first carbonyl compound of quadrivalent osmium [OsCl 5 (CO)] - is prepared by chlorination of trans-[OsX 4 (CO) 2 ] - (X = Br, I) dissolved in CH 2 Cl 2 . It is reduced immediately by Br - and I - to give [OsCl 5 (CO)] 2- . The standard potential [OsCl 5 (CO)] - / [OsCl 5 (CO)] 2- in acetonitrile referred to the saturated mercury-mercurous sulphate electrode is 0.623 V. The IR and Ra bands of [OsCl 5 (CO)] - are assigned according to point group C 4v . Compared with the corresponding Os(III) complex there is a shift to higher ...

Tópico(s): Metal complexes synthesis and properties

1986 - De Gruyter | Zeitschrift für Naturforschung B

Artigo

W. Preetz, Michael K. Manthey,

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Tópico(s): Lanthanide and Transition Metal Complexes

1993 - Wiley | ChemInform

Artigo Acesso aberto Revisado por pares

Michael Feldhaus, Richard Preetz,

Panel data on intimate relationships are becoming increasingly available, enabling a closer examination and deeper understanding of why and how they develop over time. The aim of this review is to illustrate to what extent demographic research has made progress in understanding the dynamics of intimate relationships by examining panel data. We focus on hypotheses about key transitions throughout the progression of intimate relationships, ranging from union formation up to cohabitation, marriage, ...

Tópico(s): Family Dynamics and Relationships

2021 - Federal Institute for Population Research | Comparative Population Studies

Carta Acesso aberto Revisado por pares

Meret K. Huber, Claudia Raichle, Paul Lingor, Matthis Synofzik, Stefan Borgmann, Johanna Erber, Lukas Tometten, Wolfgang Rimili, Sebastian Dolff, Kai Wille, Samuel Knauß, Christiane Piepel, Julia Lanznaster, Siegbert Rieg, Fabian Praßer, Lisa Pilgram, Annika Spottke, Thomas Klockgether, Christine Klein, Franziska Hopfner, Günter U. Höglinger,

... Braunschweig Hospital (Jan Kielstein), University Hospital Munich/LMU (Michael von Bergwelt-Baildon), University Hospital Dresden (Katja de With), University Hospital Düsseldorf (Björn Jensen), Agaplesion Diaconia Hospial Rotenburg (David Heigener), Hospital Leverkusen (Lukas Eberwein), University Hospital Saarland (Robert Bals), University Hospital Frankfurt (Maria Vehreschild), University Hospital Cologne (Norma Jung), Preetz Hospital (Helga Peetz), Hospital Fulda (Philipp Markart), Hospital ...

Tópico(s): COVID-19 Clinical Research Studies

2021 - Wiley | Movement Disorders

Artigo Acesso aberto Revisado por pares

Michael K. Manthey, W. Preetz,

Abstract The Γ 1 (A 1g ) → Γ 1 ( 3 T 1g ) luminescence spectra of mixed Cs 2 [OsCl n Br 6-n ], n = 1-5, have been measured between 15 800 and 17 000 cm -1 at 10 K. As a host lattice Cs 2 [TeCl 6 ] has been doped with purely isolated chloro-bromo-osmates(IV), including the geometrical isomers with n = 2, 3, 4. The assignments of the electronic transitions and their extensive vibronic structure are discussed.

Tópico(s): Crystal Structures and Properties

1994 - De Gruyter | Zeitschrift für Naturforschung A

Artigo

Michael Bruns, W. Preetz,

Abstract The vibrational spectra of the edge‐sharing bioctahedral title anions are assigned according to point group Dzh.

Tópico(s): Inorganic Chemistry and Materials

1986 - Wiley | Chemischer Informationsdienst

Artigo

Michael K. Manthey, W. Preetz,

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Tópico(s): Organic and Molecular Conductors Research

1994 - Wiley | ChemInform

Artigo

Michael K. Manthey, W. Preetz,

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Tópico(s): Solid-state spectroscopy and crystallography

1993 - Wiley | ChemInform

Artigo Revisado por pares

... Uta Dr. med. Kaiserslautern Holst Thomas Dr. med. Preetz Hönicke Holm Dr. med. Aue Irmisch Maik Dr. med. Köln Itzen Wilm Dr. med. Norden Jörgensen Eric Dr. med. Köln Jung-Jeschke Christa Dr. med. Bocholt Kalinski Reinhard Dr. med. Kempen Karp Udo Bonn Kilp Martin Mayen Kirchherr Hans-Joachi Dr. med. Berlin Kißkalt Peter Dr. med. Regensburg Klingel Hans Dr. med. Sigmaringen Klump Michael Dr. med. Hanau Knippert Andrea Dr. med. Kiel ...

2004 - Thieme Medical Publishers (Germany) | Zeitschrift für Gastroenterologie

Artigo Revisado por pares

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... Uta Dr. med. Kaiserslautern Holst Thomas Dr. med. Preetz Hönicke Holm Dr. med. Aue Irmisch Maik Dr. med. Köln Itzen Wilm Dr. med. Norden Jörgensen Eric Dr. med. Köln Jung-Jeschke Christa Dr. med. Bocholt Kalinski Reinhard Dr. med. Kempen Karp Udo Bonn Kilp Martin Mayen Kirchherr Hans-Joachi Dr. med. Berlin Kißkalt Peter Dr. med. Regensburg Klingel Hans Dr. med. Sigmaringen Klump Michael Dr. med. Hanau Knippert Andrea Dr. med. Kiel ...

Tópico(s): Clinical practice guidelines implementation

2004 - Thieme Medical Publishers (Germany) | Zeitschrift für Gastroenterologie