Origin of the Spin-Orbital Liquid State in a Nearly J=0 Iridate Ba3ZnIr2O9

We show using detailed magnetic and thermodynamic studies and theoretical calculations that the ground state of Ba3ZnIr2O9 is a realization of a novel spin-orbital liquid state. Our results reveal that Ba3ZnIr2O9 with Ir5+ (5d(4)) ions and strong spin-orbit coupling (SOC) arrives very close to the elusive J = 0 state but each Ir ion still possesses a weak moment. Ab initio density functional calculations indicate that this moment is developed due to superexchange, mediated by a strong intradimer hopping mechanism. While the Ir spins within the structural Ir2O9 dimer are expected to form a spin-orbit singlet state (SOS) with no resultant moment, substantial frustration arising from interdimer exchange interactions induce quantum fluctuations in these possible SOS states favoring a spin-orbital liquid phase down to at least 100 mK

Precise linear internal friction expression for a freely decaying vibrational system

From a linear motion equation, the precise linear internal friction expression for the free decay method has been deduced for the first time. A detailed comparison between the newly deduced expression and the currently used approximation has also been addressed. (C) 1997 American Institute of Physics

In situ modification of delafossite-type PdCoO2 bulk single crystal for reversible hydrogen sorption and fast hydrogen evolution

This work was financially supported by the European Research Council (ERC Advanced Grant No. 291472 'Idea Heusler') and ERC Advanced Grant (No. 742068). TOPMAT’. Electron Microscopy (C.C., D.M.) supported by the U.S. Department of Energy, Basic Energy Sciences grant No. DE-SC0019445, with facility support from the National Science Foundation NSF Grant No. DMR-1719875.The observation of extraordinarily high conductivity in delafossite-type PdCoO2 is of great current interest, and there is some evidence that electrons behave like a fluid when flowing in bulk crystals of PdCoO2. Thus, this material is an ideal platform for the study of the electron transfer processes in heterogeneous reactions. Here, we report the use of bulk single crystal PdCoO2 as a promising electrocatalyst for hydrogen evolution reactions (HERs). An overpotential of only 31 mV results in a current density of 10 mA cm-2, accompanied by excellent long-term stability. We have precisely determined that the crystal surface structure is modified after electrochemical activation with the formation of strained Pd nanoclusters in the surface layer. These nanoclusters exhibit excellent hydrogen sorption/desorption reversibility, creating more active sites for hydrogen access. The bulk PdCoO2 single crystal with ultra-high conductivity, which acts as a natural substrate for the Pd nanoclusters, provides a high-speed channel for electron transfer.Publisher PDFPeer reviewe

CCDC 101830: Experimental Crystal Structure Determination

Related Article: B.Koning, A.Meetsma, R.M.Kellogg|1998|J.Org.Chem.|63|5533|doi:10.1021/jo9806299,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 605654: Experimental Crystal Structure Determination

Related Article: O.D.Jurchescu, A.Meetsma, T.T.M.Palstra|2006|Acta Crystallogr.,Sect.B:Struct.Sci.|62|330|doi:10.1107/S010876810600305

CCDC 101828: Experimental Crystal Structure Determination

Related Article: B.Koning, A.Meetsma, R.M.Kellogg|1998|J.Org.Chem.|63|5533|doi:10.1021/jo9806299,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 703499: Experimental Crystal Structure Determination

Related Article: M.W.Bouwkamp, A.Meetsma|2009|Inorg.Chem.|48|8|doi:10.1021/ic802034m,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 605647: Experimental Crystal Structure Determination

Related Article: O.D.Jurchescu, A.Meetsma, T.T.M.Palstra|2006|Acta Crystallogr.,Sect.B:Struct.Sci.|62|330|doi:10.1107/S0108768106003053,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 703500: Experimental Crystal Structure Determination

Related Article: M.W.Bouwkamp, A.Meetsma|2009|Inorg.Chem.|48|8|doi:10.1021/ic802034m,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 703497: Experimental Crystal Structure Determination

Related Article: M.W.Bouwkamp, A.Meetsma|2009|Inorg.Chem.|48|8|doi:10.1021/ic802034m,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.