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We have investigated the electrical transport properties of nanodevices fabricated from exfoliated flakes of two-dimensional metallic ferromagnets Fe3GeTe2 (FGT) and Fe5Ge2Te2 (FG2T) down to below three layers in thickness. The per-layer anomalous Hall conductivity even in thick FGT and FG2T devices is found to be much smaller than ∼ e 2 h , the approximate value calculated for thick undoped crystals. Moreover, we obtain a power-law scaling relation between the per-layer anomalous Hall and per-layer longitudinal conductivities with an exponent close to 1.6, which agrees with the universal value for poor ferromagnetic conductors. Both FGT and FG2T devices show clear layer-dependent Curie temperatures and layer-dependent perpendicular magnetic anisotropy, with FG2T dominating the former and FGT dominating the latter for all thicknesses. Despite their declining trend as the device thickness decreases, both Curie temperature and magnetic anisotropy retain a significant fraction of their bulk values (>60% and >80% of the bulk values, respectively, even in the thinnest FG2T device), indicating attractive potential for practical applications. [ABSTRACT FROM AUTHOR]

The quinary members in the solid solution Hf2Fe1−δRu5−xIrx+δB2 (x=1–4, VE=63–66) have been investigated experimentally and computationally. They were synthesized via arc‐melting and analyzed by EDX and X‐ray diffraction. Density functional theory (DFT) calculations predicted a preference for magnetic ordering in all members, but with a strong competition between ferro‐ and antiferromagnetism arising from interchain Fe−Fe interactions. The spin exchange and magnetic anisotropy energies predicted the lowest magnetic hardness for x=1 and 3 and the highest for x=2. Magnetization measurements confirm the DFT predictions and demonstrate that the antiferromagnetic ordering (TN=55–70 K) found at low magnetic fields changed to ferromagnetic (TC=150–750 K) at higher fields, suggesting metamagnetic behavior for all samples. As predicted, Hf2FeRu3Ir2B2 has the highest intrinsic coercivity (Hc=74 kA/m) reported to date for Ti3Co5B2‐type phases. Furthermore, all coercivities outperform that of ferromagnetic Hf2FeIr5B2, indicating the importance of AFM interactions in enhancing magnetic anisotropy in these materials. Importantly, two members (x=1 and 4) maintain intrinsic coercivities in the semi‐hard range at room temperature. This study opens an avenue for controlling magnetic hardness by modulating antagonistic AFM and FM interactions in low‐dimensional rare‐earth‐free magnetic materials. [ABSTRACT FROM AUTHOR]

In an effort to explore the coordination chemistry of the coordinative sulfur centers in arachno-ruthenaborane [(Cp*Ru)2(B3H8)(CS2H)] (arachno-1), we have thermolyzed arachno-1 with group-6 metal carbonyls [M(CO)5·THF] (M = Cr, Mo and W). The reaction of arachno-1 with [Cr(CO)5·THF] resulted in the formation of hetero-trimetallic triply bridging borylene [(Cp*Ru)2(μ-CO)(μ3-CH2S2-κ2S′:κ2S′′){Cr(CO)3}(μ3-BH)] (2), bridging boryl–borylene [(Cp*Ru)2(μ-CO){(μ3-BH(CH2S2)-κ2B:κ2S′:κ1S′′)}{Cr(CO)3}(μ3-BH)] (3), and sulfido bridged hetero-trimetallic complex [(Cp*Ru)2(μ-CO)3{Cr(CO)3}(μ3-S)] (4). In 2, one side of Ru2Cr-triangle features a μ3-BH ligand while the other side is quadruply bridged by a methanedithiolato ligand in an unsymmetrical fashion. Unlike 2, in complex 3, one side of the Ru2Cr-triangle has a μ3-BH ligand while the opposite side is bridged by a boryl ligand BH(CH2S2) in an unsymmetrical way (μ3–κ2:κ2:κ1) to the metal centers. Interestingly, when the similar reactions of arachno-1 were performed with heavier group-6 metal carbonyls [M(CO)5·THF] (M = Mo and W), it led to the formation of methanedithiolato bridged hetero-trimetallic chain complexes, [{Cp*Ru(CO)}2(μ-CO)2(μ3-CH2S2-κ2S′:κ2S′′){M(CO)2}] (5, M = Mo; 6, M = W) and sulfido-bridged hetero-trimetallic complexes [(Cp*Ru)2(μ-CO)3{M(CO)3}(μ3-S)] (7, M = Mo; 8, M = W), analogous to 4. In complexes 5 and 6, a Ru2M-chain is symmetrically bridged by a methanedithiolato ligand. On the other hand, in complexes 4, 7, and 8, a sulfido ligand coordinates to two ruthenium and one group-6 metal atoms in μ3-fashion. All the complexes have been characterized by 1H NMR, 13C NMR, UV-vis, IR spectroscopy, and mass spectrometry and their structural architectures have been unambiguously established by single crystal X-ray diffraction studies. In addition, theoretical investigations provided valuable insights into their electronic structures and bonding properties. [ABSTRACT FROM AUTHOR]

The novel composition – TiFe1.3Os3.9B2.8 – is the first quaternary phase of the NbRuB structure type. The layer‐like structure consists of boron (mixed with 8 % Fe) dumbbells in the same layer as osmium atoms, some sites with mixed occupancies. The second layer has isolated boron, osmium/titanium (51 % Os) and iron atoms. The presence of iron enables the study of magnetism as Fe‐chains are present, with intra‐ and interchain distances of 3.02 Å and 5.76 Å, respectively. Density functional theory (DFT) predicts magnetic ordering to be likely with the antiferromagnetic ground state only 13 meV more favorable than the ferromagnetic state. This discovery opens the possibilities of studying various quaternary compositions in the superconducting NbRuB structure type. [ABSTRACT FROM AUTHOR]

Two new rod‐packing metal–organic frameworks (RPMOF) are constructed by regulating the in situ formation of the capping agent. In CPM‐s7, carboxylate linkers extend 1D manganese‐oxide chains in four additional directions, forming 3D RPMOF. The substitution of Mn2+ with a stronger Lewis acidic Co2+, leads to an acceleration of the hydrolysis‐prone sulfonate linker, resulting in presence of sulfate ions to reduce two out of the four carboxylate‐extending directions, and thus forming a new 2D rod‐packing CPM‐s8. Density functional theory calculations and magnetization measurements reveal ferrimagnetic ordering of CPM‐s8, signifying the potential of exploring 2D RPMOF for effective low‐dimensional magnetic materials. [ABSTRACT FROM AUTHOR]

Recent research on van der Waals (vdW) metal chalcogenides electrocatalysts for the hydrogen evolution reaction (HER) has been devoted to finding new catalysts with active basal planes. Here, we report on experimental and theoretical investigations of the HER activity of a recently discovered iron‐rich vdW spintronic material, Fe5Ge2Te2 (FG2T) in alkaline media (1 M KOH). We show that a densified electrode of FG2T requires an overpotential of only −90.5 mV to drive a current density of 10 mA/cm2. Free energy calculations of hydrogen adsorption using density functional theory (DFT) proved that the numerous sites present on the hexagonal Te layer are more active than those found in the recently proposed Fe3GeTe2 (FGT) catalyst, supporting higher activity for the new Fe‐richer catalyst. Like in FGT, XPS analysis has found that a thin oxide layer covers the active FG2T layers, suggesting the real active surface to be a hybrid FG2T/oxide layer. These results strengthen the idea of continued screening of iron‐based vdW materials to replace the non‐abundant platinum group electrocatalysts toward HER and other electrocatalytic processes. [ABSTRACT FROM AUTHOR]

Transition‐metal borides (TMBs) containing Bn‐fragment (n>3) have recently gained interest for their ability to enable exciting magnetic materials. Herein, we show that the B4‐containing TiFe0.64(1)Os2.36(1)B2 is a new ferromagnetic TMB with a Curie temperature of 523(2) K and a Weiss constant of 554(3) K, originating from the chain of M3‐triangles (M=64 %Fe+36 %Os). The new phase was synthesized from the elements by arc‐melting, and its structure was elucidated by single‐crystal X‐ray diffraction. It belongs to the Ti1+xOs2−xRuB2‐type structure (space group P6‾ 2 m, no. 189) and contains trigonal‐planar B4 boron fragments [B−B distance of 1.87(4) Å] interacting with M3‐triangles [M–M distances of 2.637(8) Å and 3.0199(2) Å]. The experimental results were supported by computational calculations based on the ideal TiFeOs2B2 composition, which revealed strong ferromagnetic interactions within and between the Fe3‐triangles. This discovery represents the first magnetically ordered Os‐rich TMB, thus it will help expand our knowledge of the role of Os in low‐dimensional magnetism of intermetallics and enable the design of such materials in the future. [ABSTRACT FROM AUTHOR]

A new ternary phase, TiIrB, was synthesized by arc-melting of the elements and characterized by powder X-ray diffraction. The compound crystallizes in the orthorhombic Ti1+xRh2−x+yIr3−yB3 structure type, space group Pbam (no. 55) with the lattice parameters a = 8.655(2), b = 15.020(2), and c = 3.2271(4) Å. Density Functional Theory (DFT) calculations were carried out to understand the electronic structure, including a Bader charge analysis. The charge distribution of TiIrB in the Ti1+xRh2−x+yIr3−yB3-type phase has been evaluated for the first time, and the results indicate that more electron density is transferred to the boron atoms in the zigzag B4 units than to isolated boron atoms. [ABSTRACT FROM AUTHOR]

Eu2Ni8Si3 and its anti‐type representative Sr2Pt3Al8 were synthesized from the elements. They crystallize in the tetragonal crystal system with space group P42/nmc and with lattice parameters of a=997.9(1) and c=747.6(1) pm (Eu2Ni8Si3) as well as a=1082.9(2) and c=823.3(2) pm (Sr2Pt3Al8). Both compounds were investigated via single crystal X‐ray diffraction, indicating slight Si/Ni mixing for the silicide. Sr2Pt3Al8 exhibits a temperature independent magnetic susceptibility, suggesting superimposed dia‐ and Pauli‐paramagnetic contributions. The independent Al and Pt sites of the platinide were further characterized by 27Al and 195Pt solid‐state NMR spectroscopy, which were assigned with the help of electronic structure calculations. ICOHP calculations and Bader charges were used to analyze the bonding situation. Eu2Ni8Si3 in contrast is paramagnetic with a ferromagnetic transition at TC=46.9(2) K and exhibits an effective magnetic moment of μeff=6.61(1) μB per Eu atom. The latter is in line with an intermediate valence that was further proven by 151Eu Mößbauer spectroscopic investigations. At 300 K, the refined Eu2+/Eu3+ ratios are 60 %/40 %, at 78 K 62 % and 38 % (Eu2+/Eu3+) are observed, being in line with the ratio deduced from the magnetic susceptibility. Finally, at 6 K a ratio of 68 % Eu2+ and 32 % Eu3+ was observed. Below the Curie temperature, the Eu2+ signal shows a full magnetic hyperfine splitting, with an internal magnetic field value of B0=28.4 T. [ABSTRACT FROM AUTHOR]

The novel composition – TiFe1.3Os3.9B2.8 – is the first quaternary phase of the NbRuB structure type. The layer‐like structure consists of boron (mixed with 8 % Fe) dumbbells in the same layer as osmium atoms, some sites with mixed occupancies. The second layer has isolated boron, osmium/titanium (51 % Os) and iron atoms. The presence of iron enables the study of magnetism as Fe‐chains are present, with intra‐ and interchain distances of 3.02 Å and 5.76 Å, respectively. Density functional theory (DFT) predicts magnetic ordering to be likely with the antiferromagnetic ground state only 13 meV more favorable than the ferromagnetic state. This discovery opens the possibilities of studying various quaternary compositions in the superconducting NbRuB structure type. [ABSTRACT FROM AUTHOR]

We have investigated the electrical transport properties of nanodevices fabricated from exfoliated flakes of two-dimensional metallic ferromagnets Fe3GeTe2 (FGT) and Fe5Ge2Te2 (FG2T) down to below three layers in thickness. The per-layer anomalous Hall conductivity even in thick FGT and FG2T devices is found to be much smaller than ∼ e 2 h , the approximate value calculated for thick undoped crystals. Moreover, we obtain a power-law scaling relation between the per-layer anomalous Hall and per-layer longitudinal conductivities with an exponent close to 1.6, which agrees with the universal value for poor ferromagnetic conductors. Both FGT and FG2T devices show clear layer-dependent Curie temperatures and layer-dependent perpendicular magnetic anisotropy, with FG2T dominating the former and FGT dominating the latter for all thicknesses. Despite their declining trend as the device thickness decreases, both Curie temperature and magnetic anisotropy retain a significant fraction of their bulk values (>60% and >80% of the bulk values, respectively, even in the thinnest FG2T device), indicating attractive potential for practical applications. [ABSTRACT FROM AUTHOR]

The quinary members in the solid solution Hf2Fe1−δRu5−xIrx+δB2 (x=1–4, VE=63–66) have been investigated experimentally and computationally. They were synthesized via arc‐melting and analyzed by EDX and X‐ray diffraction. Density functional theory (DFT) calculations predicted a preference for magnetic ordering in all members, but with a strong competition between ferro‐ and antiferromagnetism arising from interchain Fe−Fe interactions. The spin exchange and magnetic anisotropy energies predicted the lowest magnetic hardness for x=1 and 3 and the highest for x=2. Magnetization measurements confirm the DFT predictions and demonstrate that the antiferromagnetic ordering (TN=55–70 K) found at low magnetic fields changed to ferromagnetic (TC=150–750 K) at higher fields, suggesting metamagnetic behavior for all samples. As predicted, Hf2FeRu3Ir2B2 has the highest intrinsic coercivity (Hc=74 kA/m) reported to date for Ti3Co5B2‐type phases. Furthermore, all coercivities outperform that of ferromagnetic Hf2FeIr5B2, indicating the importance of AFM interactions in enhancing magnetic anisotropy in these materials. Importantly, two members (x=1 and 4) maintain intrinsic coercivities in the semi‐hard range at room temperature. This study opens an avenue for controlling magnetic hardness by modulating antagonistic AFM and FM interactions in low‐dimensional rare‐earth‐free magnetic materials. [ABSTRACT FROM AUTHOR]

Transition‐metal borides (TMBs) containing Bn‐fragment (n>3) have recently gained interest for their ability to enable exciting magnetic materials. Herein, we show that the B4‐containing TiFe0.64(1)Os2.36(1)B2 is a new ferromagnetic TMB with a Curie temperature of 523(2) K and a Weiss constant of 554(3) K, originating from the chain of M3‐triangles (M=64 %Fe+36 %Os). The new phase was synthesized from the elements by arc‐melting, and its structure was elucidated by single‐crystal X‐ray diffraction. It belongs to the Ti1+xOs2−xRuB2‐type structure (space group P6‾ 2 m, no. 189) and contains trigonal‐planar B4 boron fragments [B−B distance of 1.87(4) Å] interacting with M3‐triangles [M–M distances of 2.637(8) Å and 3.0199(2) Å]. The experimental results were supported by computational calculations based on the ideal TiFeOs2B2 composition, which revealed strong ferromagnetic interactions within and between the Fe3‐triangles. This discovery represents the first magnetically ordered Os‐rich TMB, thus it will help expand our knowledge of the role of Os in low‐dimensional magnetism of intermetallics and enable the design of such materials in the future. [ABSTRACT FROM AUTHOR]

Eu2Ni8Si3 and its anti‐type representative Sr2Pt3Al8 were synthesized from the elements. They crystallize in the tetragonal crystal system with space group P42/nmc and with lattice parameters of a=997.9(1) and c=747.6(1) pm (Eu2Ni8Si3) as well as a=1082.9(2) and c=823.3(2) pm (Sr2Pt3Al8). Both compounds were investigated via single crystal X‐ray diffraction, indicating slight Si/Ni mixing for the silicide. Sr2Pt3Al8 exhibits a temperature independent magnetic susceptibility, suggesting superimposed dia‐ and Pauli‐paramagnetic contributions. The independent Al and Pt sites of the platinide were further characterized by 27Al and 195Pt solid‐state NMR spectroscopy, which were assigned with the help of electronic structure calculations. ICOHP calculations and Bader charges were used to analyze the bonding situation. Eu2Ni8Si3 in contrast is paramagnetic with a ferromagnetic transition at TC=46.9(2) K and exhibits an effective magnetic moment of μeff=6.61(1) μB per Eu atom. The latter is in line with an intermediate valence that was further proven by 151Eu Mößbauer spectroscopic investigations. At 300 K, the refined Eu2+/Eu3+ ratios are 60 %/40 %, at 78 K 62 % and 38 % (Eu2+/Eu3+) are observed, being in line with the ratio deduced from the magnetic susceptibility. Finally, at 6 K a ratio of 68 % Eu2+ and 32 % Eu3+ was observed. Below the Curie temperature, the Eu2+ signal shows a full magnetic hyperfine splitting, with an internal magnetic field value of B0=28.4 T. [ABSTRACT FROM AUTHOR]

The metal borides, Hf 2 MOs 5 B 2 (M = Mn, Fe, Co), which are the first Os-rich quaternary variants of the prolific Ti 3 Co 5 B 2 structure type, were investigated computationally and experimentally. In their crystal structures, osmium builds a network of prisms, in which the other elements are located. The magnetic M elements are found in face-connected Os 8 square prisms leading to M-chains with intra- and interchain distances of about 3.0 and 6.5 Å, respectively. Density functional theory (DFT) showed that magnetic ordering is hugely favored for M = Mn and Fe but only slightly favored for M = Co. Experimental investigations then confirmed and extended the DFT predictions as a metamagnetic behavior was found for the M = Mn and Fe phases, whereby the antiferromagnetic interactions ( T N = 19 and 90 K) found at low magnetic fields change to ferromagnetic at higher fields. A very broad transition ( T N = 45 K) is found for M = Co, suggesting spin-glass behavior for this phase. For M = Fe, a hard-magnet hysteresis at 5 K is found with a 40 kA/m coercivity, and even at room temperature, a significant hysteresis is found. This study paves the way for the discovery of Os-based magnets in this structure type and other intermetallics.

The quinary members in the solid solution Hf 2 Fe 1-δ Ru 5-x Ir x+δ B 2 (x=1-4, VE=63-66) have been investigated experimentally and computationally. They were synthesized via arc-melting and analyzed by EDX and X-ray diffraction. Density functional theory (DFT) calculations predicted a preference for magnetic ordering in all members, but with a strong competition between ferro- and antiferromagnetism arising from interchain Fe-Fe interactions. The spin exchange and magnetic anisotropy energies predicted the lowest magnetic hardness for x=1 and 3 and the highest for x=2. Magnetization measurements confirm the DFT predictions and demonstrate that the antiferromagnetic ordering (T N =55-70 K) found at low magnetic fields changed to ferromagnetic (T C =150-750 K) at higher fields, suggesting metamagnetic behavior for all samples. As predicted, Hf 2 FeRu 3 Ir 2 B 2 has the highest intrinsic coercivity (H c =74 kA/m) reported to date for Ti 3 Co 5 B 2 -type phases. Furthermore, all coercivities outperform that of ferromagnetic Hf 2 FeIr 5 B 2 , indicating the importance of AFM interactions in enhancing magnetic anisotropy in these materials. Importantly, two members (x=1 and 4) maintain intrinsic coercivities in the semi-hard range at room temperature. This study opens an avenue for controlling magnetic hardness by modulating antagonistic AFM and FM interactions in low-dimensional rare-earth-free magnetic materials., (© 2023 Wiley-VCH GmbH.)

In an effort to explore the coordination chemistry of the coordinative sulfur centers in arachno -ruthenaborane [(Cp*Ru) 2 (B 3 H 8 )(CS 2 H)] ( arachno -1), we have thermolyzed arachno -1 with group-6 metal carbonyls [M(CO) 5 ·THF] (M = Cr, Mo and W). The reaction of arachno -1 with [Cr(CO) 5 ·THF] resulted in the formation of hetero-trimetallic triply bridging borylene [(Cp*Ru) 2 (μ-CO)(μ 3 -CH 2 S 2 -κ 2 S':κ 2 S''){Cr(CO) 3 }(μ 3 -BH)] (2), bridging boryl-borylene [(Cp*Ru) 2 (μ-CO){(μ 3 -BH(CH 2 S 2 )-κ 2 B:κ 2 S':κ 1 S'')}{Cr(CO) 3 }(μ 3 -BH)] (3), and sulfido bridged hetero-trimetallic complex [(Cp*Ru) 2 (μ-CO) 3 {Cr(CO) 3 }(μ 3 -S)] (4). In 2, one side of Ru 2 Cr-triangle features a μ 3 -BH ligand while the other side is quadruply bridged by a methanedithiolato ligand in an unsymmetrical fashion. Unlike 2, in complex 3, one side of the Ru 2 Cr-triangle has a μ 3 -BH ligand while the opposite side is bridged by a boryl ligand BH(CH 2 S 2 ) in an unsymmetrical way (μ 3 -κ 2 :κ 2 :κ 1 ) to the metal centers. Interestingly, when the similar reactions of arachno -1 were performed with heavier group-6 metal carbonyls [M(CO) 5 ·THF] (M = Mo and W), it led to the formation of methanedithiolato bridged hetero-trimetallic chain complexes, [{Cp*Ru(CO)} 2 (μ-CO) 2 (μ 3 -CH 2 S 2 -κ 2 S':κ 2 S''){M(CO) 2 }] (5, M = Mo; 6, M = W) and sulfido-bridged hetero-trimetallic complexes [(Cp*Ru) 2 (μ-CO) 3 {M(CO) 3 }(μ 3 -S)] (7, M = Mo; 8, M = W), analogous to 4. In complexes 5 and 6, a Ru 2 M-chain is symmetrically bridged by a methanedithiolato ligand. On the other hand, in complexes 4, 7, and 8, a sulfido ligand coordinates to two ruthenium and one group-6 metal atoms in μ 3 -fashion. All the complexes have been characterized by 1 H NMR, 13 C NMR, UV-vis, IR spectroscopy, and mass spectrometry and their structural architectures have been unambiguously established by single crystal X-ray diffraction studies. In addition, theoretical investigations provided valuable insights into their electronic structures and bonding properties.

The complex metal-rich boride Ti 5- x Fe 1- y Os 6+ x+y B 6 (0 < x , y < 1), crystallizing in a new structure type (space group Cmcm , no. 63), was prepared by arc-melting. The new structure contains both isolated boron atoms and zigzag boron chains (B-B distance of 1.74 Å), a rare combination among metal-rich borides. In addition, the structure also contains Fe-chains running parallel to the B-chains. Unlike in previously reported structures, these Fe-chains are offset from each other and arranged in a triangular manner with intrachain and interchain distances of 2.98 and 6.69 Å, respectively. Density functional theory (DFT) calculations predict preferred ferromagnetic interactions within each chain but only small energy differences for different magnetic interactions between them, suggesting a potentially weak long-range order. This new structure offers the opportunity to study new configurations and interactions of magnetic elements for the design of magnetic materials.

Two new rod-packing metal-organic frameworks (RPMOF) are constructed by regulating the in situ formation of the capping agent. In CPM-s7, carboxylate linkers extend 1D manganese-oxide chains in four additional directions, forming 3D RPMOF. The substitution of Mn 2+ with a stronger Lewis acidic Co 2+ , leads to an acceleration of the hydrolysis-prone sulfonate linker, resulting in presence of sulfate ions to reduce two out of the four carboxylate-extending directions, and thus forming a new 2D rod-packing CPM-s8. Density functional theory calculations and magnetization measurements reveal ferrimagnetic ordering of CPM-s8, signifying the potential of exploring 2D RPMOF for effective low-dimensional magnetic materials., (© 2022 Wiley-VCH GmbH.)

Transition-metal borides (TMBs) containing B n -fragment (n>3) have recently gained interest for their ability to enable exciting magnetic materials. Herein, we show that the B 4 -containing TiFe 0.64(1) Os 2.36(1) B 2 is a new ferromagnetic TMB with a Curie temperature of 523(2) K and a Weiss constant of 554(3) K, originating from the chain of M 3 -triangles (M=64 %Fe+36 %Os). The new phase was synthesized from the elements by arc-melting, and its structure was elucidated by single-crystal X-ray diffraction. It belongs to the Ti 1+x Os 2-x RuB 2 -type structure (space group P 6 ‾ 2 m, no. 189) and contains trigonal-planar B 4 boron fragments [B-B distance of 1.87(4) Å] interacting with M 3 -triangles [M-M distances of 2.637(8) Å and 3.0199(2) Å]. The experimental results were supported by computational calculations based on the ideal TiFeOs 2 B 2 composition, which revealed strong ferromagnetic interactions within and between the Fe 3 -triangles. This discovery represents the first magnetically ordered Os-rich TMB, thus it will help expand our knowledge of the role of Os in low-dimensional magnetism of intermetallics and enable the design of such materials in the future., (© 2022 Wiley-VCH GmbH.)