crystal structures of the participating metal components. An intermetallic compound is formed when the bonds between the dissimilar atoms are stronger than the bonds between the atoms of the same element.Because of their specific structure, intermetallic compounds usually exhibit unique physical and chemical properties that are potentially superior to their disordered alloy analogues and the pure metals. Such properties include, for example, magnetoresistance, [3,4] superconductivity, [5][6][7] enhanced catalytic activity, [8,9] and hydrogen storage capability. [10] Intermetallics and alloys containing Co or Ni and Sn with varying stoichiometry have mostly been studied as anode materials for Li-and Na-ion batteries. [11][12][13][14][15][16][17][18][19] As ferromagnetic materials, they also show potential for magnetic devices. [20][21][22] Furthermore, intermetallic Co-Sn and Ni-Sn compounds have also been studied for catalytic purposes. [23][24][25][26] For future applications like nanoelectronic devices, it is pivotal to be able to control the thickness and composition of thin films with sub-nanometer accuracy. Atomic layer deposition (ALD) is a thin film preparation method based on repeated, saturative, and irreversible surface reactions between alternately supplied gaseous precursors ensuring self-limiting growth of the desired material. [27,28] Owing to the self-limiting growth mechanism, ALD can be used to deposit uniform thin films over complex structures in a controlled and reproducible manner. No previous reports on the ALD of intermetallic Co 3 Sn 2 or Ni 3 Sn 2 thin films are found in the literature, and the ALD of other intermetallic compounds has also been scarce if existent at all. Intermetallic phases in Pt-In, [29] Pt-Sn, [30] and Ni-Fe [31] systems have been obtained by the postdeposition reduction of the corresponding ALD oxides. There are also some ALD studies on metal alloys, such as Pt-Ir, [32] Pd-Pt, [33][34][35] Ru-Pt, [36] Ru-Co, [37] Co-W, [38,39] Co-Pt, [40] Ru-Mn, [41] and Cu-Mn, [42] but no reports exist on materials exhibiting a specific intermetallic structure. Co-Sn and Ni-Sn with varying stoichiometry, including the intermetallic Co 3 Sn 2 and Ni 3 Sn 2 phases, have generally been prepared by, for example, ball Intermetallics form a versatile group of materials that possess unique properties ranging from superconductivity to giant magnetoresistance. The intermetallic Co-Sn and Ni-Sn compounds are promising materials for magnetic applications as well as for anodes in lithium-and sodium-ion batteries. Herein, a method is presented for the preparation of Co 3 Sn 2 and Ni 3 Sn 2 thin films using diamine adducts of cobalt(II) and nickel(II) chlorides, CoCl 2 (TMEDA) and NiCl 2 (TMPDA) (TMEDA = N,N,N′,N′tetramethylethylenediamine, TMPDA = N,N,N′,N′-tetramethyl-1,3propanediamine) combined with tributyltin hydride. The films are grown by atomic layer deposition (ALD), a technique that enables conformal film deposition with sub-nanometer thickness control. The Co 3 Sn 2 process fulfills the ...

Classical and quantum phase transitions (QPTs), with their accompanying concepts of criticality and universality, are a cornerstone of statistical thermodynamics. An exemplary controlled QPT is the field-induced magnetic ordering of a gapped quantum magnet. Although numerous "quasi-one-dimensional" coupled spin-chain and -ladder materials are known whose ordering transition is three-dimensional (3D), quasi-2D systems are special for several physical reasons. Motivated by the ancient pigment Han Purple (BaCuSi2O6), a quasi-2D material displaying anomalous critical properties, we present a complete analysis of Ba0.9Sr0.1CuSi2O6. We measure the zero-field magnetic excitations by neutron spectroscopy and deduce the magnetic Hamiltonian. We probe the field-induced transition by combining magnetization, specific-heat, torque and magnetocalorimetric measurements with low-temperature nuclear magnetic resonance studies near the QPT. By a Bayesian statistical analysis and large-scale Quantum Monte Carlo simulations, we demonstrate unambiguously that observable 3D quantum critical scaling is restored by the structural simplification arising from light Srsubstitution in Han Purple.

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This article describes the atomic layer deposition (ALD) of nickel nitride and nickel thin films using a diamine adduct of Ni(II) chloride, NiCl 2 (TMPDA) (TMPDA ¼ N,N,N 0 ,N 0 ,-tetramethyl-1,3-propanediamine), as the metal precursor. Owing to the high reducing power of tert-butylhydrazine (TBH), the films are grown at low temperatures of 190-250 C. This is one of the few lowtemperature ALD processes that can be used to grow Ni 3 N and Ni metal on both insulating and conductive substrates. The films are characterized in terms of crystallinity, morphology, composition, resistivity, and coercivity. Xray diffraction shows reflections compatible with either hexagonal Ni or Ni 3 N. Composition analyses suggest that the films are close to stoichiometric Ni 3 N. Despite the nitride component, the films exhibit low resistivity values and at the lowest, a resistivity of 37 μΩ cm is achieved. The result is lower than what is typically observed for Ni x N films and not much higher than the best results concerning ALD Ni metal. The nitrogen content of the films is lowered down to 1.2 at% by postdeposition reduction at 150 C in 10% forming gas. After the reduction, the nonmagnetic nitride films are converted to ferromagnetic Ni metal.

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