cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.34816/ifao.archives.232663
title: SAQQARA_pv_2004_00702

description: Référence : pv_2004_00702<br />Site : Saqqara<br />Secteur : Mastaba de Ti<br />Type : photographie<br />
DOI: 10.3535/ehj-1p8-gcp
title: Astelia alpina R.Br.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/m3n-shc-c2w
title: Ranunculus binatus Rchb.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2310007-4
title: The behaviour of LaMnO3 and LaMnO3+δ at high pressure

description: LaMnO3 is the parent compound of a family of doped manganates that exhibit a range of electronic phases and unusual properties with potential applications in new electronic devices. LaMnO3 crystallises in the orthorhombically distorted perovskite structure (Pbmn), in which every Mn3+ ion with high-spin configuration is surrounded by an octahedron of six oxygen ligands. Under ambient conditions, the Jahn-Teller (JT) instability of the singly occupied eg orbitals gives rise to cooperative distortions of the MnO6 octahedral units, resulting in orbital ordering and the insulating behaviour of LaMnO3. It is teh aim of this proposal to investigate as to how pressure alters the MnO6 octyahrdra distortion in LaMnO3 and the related material LaMNO3+δ in which no Jahn Teller instabilities are observed.
DOI: 10.5286/isis.e.rb2310440
title: Crystal field excitations of new low energy spin-1/2 triangular antiferromagnets

description: Despite being frustrated, the triangular lattice antiferromagnet is expected to develop long-range magnetic order and spin-wave excitations at low temperatures. Theoretical studies suggest that the magnetic spectrum shows small deviations with respect to linear spin-wave theory with the band of excitations expected to be renormalized downward and broadened for the case of quantum spin-1/2. In contrast recent experiments on the spin-1/2 triangular antiferromagnet Ba3CoSb2O9 reveal major differences between the measured excitations and spin-wave theory, including 3 bands of excitations and a continuum that extends to much higher energies (6 times the exchange energy). Because of the unexpected nature of these results it is necessary to verify them in other materials, thus we plan to investigate the spectrum of the new effective spin-1/2 triangular lattice antiferromagnets Ba3CoNb2O9 and Ba3CoTa2O9. We also plan to investigate the crystal field levels of their magnetic Co2+ ions to determine their ground state wavefunction and identify the presence of any anisotropies.
DOI: 10.5286/isis.e.rb2310440-1
title: Crystal field excitations of new low energy spin-1/2 triangular antiferromagnets

description: Despite being frustrated, the triangular lattice antiferromagnet is expected to develop long-range magnetic order and spin-wave excitations at low temperatures. Theoretical studies suggest that the magnetic spectrum shows small deviations with respect to linear spin-wave theory with the band of excitations expected to be renormalized downward and broadened for the case of quantum spin-1/2. In contrast recent experiments on the spin-1/2 triangular antiferromagnet Ba3CoSb2O9 reveal major differences between the measured excitations and spin-wave theory, including 3 bands of excitations and a continuum that extends to much higher energies (6 times the exchange energy). Because of the unexpected nature of these results it is necessary to verify them in other materials, thus we plan to investigate the spectrum of the new effective spin-1/2 triangular lattice antiferromagnets Ba3CoNb2O9 and Ba3CoTa2O9. We also plan to investigate the crystal field levels of their magnetic Co2+ ions to determine their ground state wavefunction and identify the presence of any anisotropies.
DOI: 10.3535/3fc-4es-62d
title: Eucalyptus L'Hér.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2220540
title: Spin fluctuation spectrum in high-quality single crystals of the new iron-based superconductor LuFe2Ge2
DOI: 10.5286/isis.e.rb2220540-3
title: Spin fluctuation spectrum in high-quality single crystals of the new iron-based superconductor LuFe2Ge2
DOI: 10.5286/isis.e.rb2310088
title: Investigating possible quantum-spin-liquid state in Nb3Cl8 using Muon spin relaxation

description: Cluster magnets may provide new insights in searching quantum spin liquids (QSLs). The cluster magnet Nb3Cl8 consists of S=1/2 Nb trimmers, which form an emergent triangular lattice. The system shows a paramagnetic-to-non-magnetic transition at about 100 K. Recently, it has been shown that the high-temperature electronic state is an excellent single-band Mott insulator, which raises the question whether its ground state is a QSL since the insulating QSL is born as a Mott insulator. We have found that the magnetic phase can be maintained down to lowest temperature if the single crystals are ground into powders. The low temperature-specific measurements show that the magnetic system is not ordered down to 50 mK, and has a large T-linear term with C/T (T-&gt;0) ~ 0.2 J/mol K^2. These results suggest that the magnetic phase of Nd3Cl8 may host a QSL. We thus propose to study it on MuSR to confirm the QSL behaviour.
DOI: 10.5286/isis.e.rb2310088-1
title: Investigating possible quantum-spin-liquid state in Nb3Cl8 using Muon spin relaxation

description: Cluster magnets may provide new insights in searching quantum spin liquids (QSLs). The cluster magnet Nb3Cl8 consists of S=1/2 Nb trimmers, which form an emergent triangular lattice. The system shows a paramagnetic-to-non-magnetic transition at about 100 K. Recently, it has been shown that the high-temperature electronic state is an excellent single-band Mott insulator, which raises the question whether its ground state is a QSL since the insulating QSL is born as a Mott insulator. We have found that the magnetic phase can be maintained down to lowest temperature if the single crystals are ground into powders. The low temperature-specific measurements show that the magnetic system is not ordered down to 50 mK, and has a large T-linear term with C/T (T-&gt;0) ~ 0.2 J/mol K^2. These results suggest that the magnetic phase of Nd3Cl8 may host a QSL. We thus propose to study it on MuSR to confirm the QSL behaviour.
DOI: 10.34816/ifao.archives.232664
title: SAQQARA_pv_2004_00703

description: Référence : pv_2004_00703<br />Site : Saqqara<br />Secteur : Mastaba de Ti<br />Type : photographie<br />
DOI: 10.3535/dtk-vsh-q82
title: Astelia menziesiana Sm.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/qhs-06l-75k
title: Astelia menziesiana Sm.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2310645
title: Diffuse scattering from hidden magnetic order in frustrated hexagonal ytterium manganite

description: This proposal concerns the search for hidden magnetic order within a highly frustrated magnetic system. Our recent inelastic neutron study of h-YMnO3 reveal strong diffuse magnetic fluctuations above and below the Néel temperature. Our extensive simulations of the magnetic order of h-YMnO3 reveal that this rich and intricate diffuse magnetic scattering arise from a network of two coexisting but non-interacting magnetic clusters. The first of which is well known but the second has not yet been reported and is thus "hidden". To provide crucial evidence for this hidden order, we propose to map the full spin-wave spectrum of h-YMnO3.
DOI: 10.5286/isis.e.rb2310645-1
title: Diffuse scattering from hidden magnetic order in frustrated hexagonal ytterium manganite

description: This proposal concerns the search for hidden magnetic order within a highly frustrated magnetic system. Our recent inelastic neutron study of h-YMnO3 reveal strong diffuse magnetic fluctuations above and below the Néel temperature. Our extensive simulations of the magnetic order of h-YMnO3 reveal that this rich and intricate diffuse magnetic scattering arise from a network of two coexisting but non-interacting magnetic clusters. The first of which is well known but the second has not yet been reported and is thus "hidden". To provide crucial evidence for this hidden order, we propose to map the full spin-wave spectrum of h-YMnO3.
DOI: 10.3535/8vf-21s-qyb
title: Astelia menziesiana Sm.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/fww-m12-w2k
title: Astelia menziesiana Sm.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2310018
title: Confinement-induced local nuclear dynamics of protons in benzene confined in MCM-41.

description: VESUVIO is a unique neutron beamline enabling critical appraisal of confinement-induced local nuclear chemical dynamics in condensed matter and molecular systems. Due to reduced dimensionality and large surface and interface effects, liquids that are subjected to some geometric constraints on the nanoscale can have different properties to those they display under standard bulk conditions. We have found that the nanoscale confinement of benzene has a major effect on the spatial and orientational correlations observed between the molecules when compared with the structure of the bulk liquid. These differences are most marked for molecules in parallel configurations, and this suggests differences in chemical reactivity between the confined and bulk liquids. In order to extend the aforementioned research methodology and capitalise on the direct link between the local structure and dynamics of confined molecular liquid species, in this proposal, we would like to employ the full functionality of the VESUVIO beamline to measure concurrently incident neutron energy-dependant sample transmission (NT), and atom-resolved neutron Compton scattering (NCS) in two isotopologues, benzene and benzene-d6, as well as in benzene and benzene-d6 both confined in the pores of a Pt/MCM-41 catalyst.
DOI: 10.5286/isis.e.rb2310018-1
title: Confinement-induced local nuclear dynamics of protons in benzene confined in MCM-41.

description: VESUVIO is a unique neutron beamline enabling critical appraisal of confinement-induced local nuclear chemical dynamics in condensed matter and molecular systems. Due to reduced dimensionality and large surface and interface effects, liquids that are subjected to some geometric constraints on the nanoscale can have different properties to those they display under standard bulk conditions. We have found that the nanoscale confinement of benzene has a major effect on the spatial and orientational correlations observed between the molecules when compared with the structure of the bulk liquid. These differences are most marked for molecules in parallel configurations, and this suggests differences in chemical reactivity between the confined and bulk liquids. In order to extend the aforementioned research methodology and capitalise on the direct link between the local structure and dynamics of confined molecular liquid species, in this proposal, we would like to employ the full functionality of the VESUVIO beamline to measure concurrently incident neutron energy-dependant sample transmission (NT), and atom-resolved neutron Compton scattering (NCS) in two isotopologues, benzene and benzene-d6, as well as in benzene and benzene-d6 both confined in the pores of a Pt/MCM-41 catalyst.
DOI: 10.5286/isis.e.rb2310669-1
title: Librational contributions to entropy in barocaloric quinuclidinium salts

description: Barocaloric materials are a promising new environmentally friendly refrigeration technology, allowing heat to be pumped using phase transitions associated with large entropy changes. However, the atomic origins of these entropy changes are poorly understood at present, limiting the opportunities to engineer these materials. We have recently shown that phonons, in particular low-energy molecular librational modes, give major contributions to the entropy change even for materials with apparently pure order-disorder transitions. Here we will use TOSCA to measure the phonon density of states of a new family of barocaloric materials, the quinuclidinium salts, to investigate their large entropy changes, focusing on the low-energy librations at low temperature. We have separately applied for MAPS time to understand the changes in the hydrogen bonding network at high energy transfers. Our results will not only be invaluable for understanding this particular material and its immediate family, but will demonstrate the power of inelastic neutron scattering for understanding molecular barocalorics, even when deuteration is impractical.
DOI: 10.34816/ifao.archives.232665
title: SAQQARA_pv_2004_00704

description: Référence : pv_2004_00704<br />Site : Saqqara<br />Secteur : Mastaba de Ti<br />Type : photographie<br />
DOI: 10.3535/65n-gd7-zmf
title: Leucanthemopsis alpina (L.) Heywood

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/hty-z3p-413
title: Leucanthemopsis alpina (L.) Heywood

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2300084-1
title: Neutron scattering of a potential room temperature van der Waals antiferromagnet

description: The lack of air-stability and the absence of near room temperature (RT) magnetic ordering remain key roadblocks for the wide-range use of 2D magnets in spintronics. We have synthesized an air-stable, easily exfoliable and high mobility 2D vdW single crystals and powder samples of TaCo2Te2 that have shown indications for long-range AFM ordering at RT as discussed below. We observed distinct first-order transitions in magnetic susceptibility vs temperature plots near 380 K and 560 K (Figure 1c) in multiple TaCo2Te2 crystals which could correspond to high temperature Néel transitions or structural transitions. We have synthesized a phase pure TaCo2Te2 powder sample weighing around 0.5 grams specifically for neutron scattering measurements which also maintain phase stability at elevated temperatures in vacuum sealed setup. The general description of spin ordering in TaCo2Te2 requires more sensitive probing techniques such as neutron scattering for acquiring conclusive evidence of AFM ordering. The goal of the neutron scattering measurements is twofold : (1) to confirm the existence and nature of AFM ordering in TaCo2Te2 near/beyond the room temperature and to explore the magneto-structural transitions observed in the magnetization data around 400 and 550 K; (2) to understand the coupling between the Peierls distortion and the magnetic ordering in TaCo2Te2. To perform the experimental plan detailed above we request 1 day of beam time considering set up and temperature changes.
DOI: 10.5286/isis.e.rb2310669
title: Librational contributions to entropy in barocaloric quinuclidinium salts

description: Barocaloric materials are a promising new environmentally friendly refrigeration technology, allowing heat to be pumped using phase transitions associated with large entropy changes. However, the atomic origins of these entropy changes are poorly understood at present, limiting the opportunities to engineer these materials. We have recently shown that phonons, in particular low-energy molecular librational modes, give major contributions to the entropy change even for materials with apparently pure order-disorder transitions. Here we will use TOSCA to measure the phonon density of states of a new family of barocaloric materials, the quinuclidinium salts, to investigate their large entropy changes, focusing on the low-energy librations at low temperature. We have separately applied for MAPS time to understand the changes in the hydrogen bonding network at high energy transfers. Our results will not only be invaluable for understanding this particular material and its immediate family, but will demonstrate the power of inelastic neutron scattering for understanding molecular barocalorics, even when deuteration is impractical.
DOI: 10.5286/isis.e.rb2390184-1
title: Ordering in a Fe-Co-Ti alloy
DOI: 10.3535/d1d-fyz-v5g
title: Chrysanthemum coronopifolium Vill.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/fsx-r8l-686
title: Eucalyptus L'Hér.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2300084
title: Neutron scattering of a potential room temperature van der Waals antiferromagnet

description: The lack of air-stability and the absence of near room temperature (RT) magnetic ordering remain key roadblocks for the wide-range use of 2D magnets in spintronics. We have synthesized an air-stable, easily exfoliable and high mobility 2D vdW single crystals and powder samples of TaCo2Te2 that have shown indications for long-range AFM ordering at RT as discussed below. We observed distinct first-order transitions in magnetic susceptibility vs temperature plots near 380 K and 560 K (Figure 1c) in multiple TaCo2Te2 crystals which could correspond to high temperature Néel transitions or structural transitions. We have synthesized a phase pure TaCo2Te2 powder sample weighing around 0.5 grams specifically for neutron scattering measurements which also maintain phase stability at elevated temperatures in vacuum sealed setup. The general description of spin ordering in TaCo2Te2 requires more sensitive probing techniques such as neutron scattering for acquiring conclusive evidence of AFM ordering. The goal of the neutron scattering measurements is twofold : (1) to confirm the existence and nature of AFM ordering in TaCo2Te2 near/beyond the room temperature and to explore the magneto-structural transitions observed in the magnetization data around 400 and 550 K; (2) to understand the coupling between the Peierls distortion and the magnetic ordering in TaCo2Te2. To perform the experimental plan detailed above we request 1 day of beam time considering set up and temperature changes.
DOI: 10.5286/isis.e.rb2310269
title: Structural Investigations of Low Thermal Conductivity Materials

description: We wish to exploit the ability of neutrons to locate light atoms in the presence of heavy atoms to investigate the structural properties of new defect pyrochlores with low thermal conductivity that are designed to act as thermal insulation in thermal batteries. Using ion exchange techniques, we have produced mixed ammonium-caesium materials [(NH4)1-xCsxTa1-yNbyWO6 0
DOI: 10.5286/isis.e.rb2310269-1
title: Structural Investigations of Low Thermal Conductivity Materials

description: We wish to exploit the ability of neutrons to locate light atoms in the presence of heavy atoms to investigate the structural properties of new defect pyrochlores with low thermal conductivity that are designed to act as thermal insulation in thermal batteries. Using ion exchange techniques, we have produced mixed ammonium-caesium materials [(NH4)1-xCsxTa1-yNbyWO6 0
DOI: 10.34816/ifao.archives.232666
title: SAQQARA_pv_2004_00705

description: Référence : pv_2004_00705<br />Site : Saqqara<br />Secteur : Mastaba de Ti<br />Type : photographie<br />
DOI: 10.3535/gg4-d15-075
title: Leucanthemum pallens (J. Gay ex Perreym.) DC.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.3535/h2w-lbr-t9f
title: Nananthea perpusilla (Loisel.) DC.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.
DOI: 10.5286/isis.e.rb2310227
title: Towards a comprehensive interpretation of wavelength dependent attenuation coefficients: The effect of dislocation densities

description: Hydrogen embrittlement in metal alloy can generate microstructural change, resulting in residual stress in the bulk. However, the quantitative measurement on H-uptake is very challenge due to very low sensitivity of common analytical technique. Prior to the understanding of H-uptake in metal alloy, an underlying behavior of stress-strain in metal alloy should be studied. Defects and dislocations in metal alloys using neutron transmission has been found limited. Since neutron transmission can probe a sample in a large volume at once compared to neutron scattering, diffraction, and spectroscopy, it is useful to obtain a stress-strain mapping in the sample which results in more underlying knowledge on defect distribution. In addition, an in-situ measurement would allow us to study an evolution of stress and to quantitatively measure how neutron transmission coefficient correlates to the residual stress. The proposed study will study on a Medium manganese steel established in the 3rd generation high strength steel (AHSS) as well as a low carbon steel as a reference material.
DOI: 10.5286/isis.e.rb2310227-1
title: Towards a comprehensive interpretation of wavelength dependent attenuation coefficients: The effect of dislocation densities

description: Hydrogen embrittlement in metal alloy can generate microstructural change, resulting in residual stress in the bulk. However, the quantitative measurement on H-uptake is very challenge due to very low sensitivity of common analytical technique. Prior to the understanding of H-uptake in metal alloy, an underlying behavior of stress-strain in metal alloy should be studied. Defects and dislocations in metal alloys using neutron transmission has been found limited. Since neutron transmission can probe a sample in a large volume at once compared to neutron scattering, diffraction, and spectroscopy, it is useful to obtain a stress-strain mapping in the sample which results in more underlying knowledge on defect distribution. In addition, an in-situ measurement would allow us to study an evolution of stress and to quantitatively measure how neutron transmission coefficient correlates to the residual stress. The proposed study will study on a Medium manganese steel established in the 3rd generation high strength steel (AHSS) as well as a low carbon steel as a reference material.
DOI: 10.5286/isis.e.rb2310243-1
title: Exploring the low energy excitations of the S=1 quasi-1D molecular system Mo3Se7(dmit)3

description: The molecular magnetic system Mo3S7(dmit)3 is a semiconductor with a charge gap of around 100 K and no magnetic transition or spin freezing down to 50 mK. In the crystal structure the molecules form closely coupled triangles and these triangular units are arranged in hexagonal layers. Theoretical studies indicate that each of the triangles has spin 1 and that the in-plane coupling between triangles is very weak compared to the inter-plane coupling of the triangles. The system can thus be viewed as a strong-rung three-leg spin ladder which is expected to behave as a symmetry-protected topological phase with a Haldane spin gap on the order of 1 K. Temperature dependent muSR studies in longitudinal fields up to 2 T have observed a gap feature that closes with field, becoming zero at around 1.2 T. This is consistent with the expectation for such a Haldane spin chain. This study will explore the properties of the isostructural system Mo3Se7(dmit)3 which is also expected to have a Haldane-gapped state at low field, with gap closure at a quantum critical point reached by a field that will be comfortably within the range of the HiFi instrument.
DOI: 10.3535/5xh-c48-mwh
title: Astelia menziesiana Sm.

description: Digital Specimen for the physical specimen hosted at Botanic Garden and Botanical Museum Berlin.