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C17H19F2N3O5S, monoclinic, P21/c (no. 14), a = 14.157(7) Å, b = 11.133(6) Å, c = 11.400(6) Å, β = 91.965(13)°, V = 1795.6(16) Å3, Z = 4, Rgt(F) = 0.0611 wRref(F2) = 0.1809, T = 205 K. [ABSTRACT FROM AUTHOR]

The development of novel phosphors with excellent luminescence properties for white light-emitting diodes (WLEDs) is always a formidable task. Compared with the traditional laborious and aimless "trial and error" experiments, a mineral-inspired prototype strategy can provide an efficient and accurate method. Herein, for the first time, a novel yellow-emitting phosphor NaBaY2(PO4)3:Eu2+ was discovered using the mineral-inspired prototype strategy and cation substitution method. The phosphor was prepared via the high-temperature solid-state reaction method, and its crystal structure, luminescence properties and potential application for WLEDs were systematically investigated. The NaBaY2(PO4)3 phase was derived from the K2Mg2(SO4)3-type mineral structure and a photoluminescence study revealed that the phosphor can emit bright yellow light with a maximum at 545 nm upon excitation at 351 nm. A WLED lamp was fabricated by the use of a blend of commercial blue-emitting BaMgAl10O17:Eu2+, yellow-emitting NaBaY2(PO4)3:Eu2+ and red-emitting (Ca, Sr)AlSiN3:Eu2+ phosphors with a 380 nm LED chip. The CIE, CCT, Ra and efficiency of the as-fabricated LEDs were measured to be equal to (0.366, 0.365), 4327 K, 91.2 and 40.8 lm W−1, respectively. These results suggest that NaBaY2(PO4)3:Eu2+ could be a promising candidate for n-UV WLEDs. [ABSTRACT FROM AUTHOR]

The SrCoO3−δ system has broad application potential due to its diverse crystal structures, oxidation stoichiometric ratio, and significant electrical and magnetic properties. However, it faces the challenges of a complex crystal structure and oxygen defect control in this material system. Herein, we introduce oxygen defects into SrCoO3−δvia Er doping to regulate the structural, electrical and magnetic transport properties. Sr1−xErxCoO3−δ (x = 0–0.25) undergoes an evolution of structure and oxygen content (measured using the iodometric method) from hexagonal SrCoO2.626 (H + Co3O4) to cubic perovskite Sr0.9Er0.1CoO2.689 (CP) and finally to ordered tetragonal Sr0.8Er0.2CoO2.635 (OT). Among the three phases, Sr0.9Er0.1CoO2.689 (CP) exhibits the lowest resistivity, only 4.06 mΩ cm at room temperature, which is attributed to its high three-dimensional symmetry, overlap of O 2p and Co 3d orbitals at high oxygen ion concentration. Further introduction of Er ions and oxygen defects promotes the transformation from low spin Co4+ (LS, t 52g e 0g , S = 1/2) to high spin Co3+ (HS, t 42g e 2g , S = 2), and from the CoO6 octahedron (low magnetic moment transformation) to the CoO4.25 tetrahedron (high magnetic moment). The oxygen-deficient CoO4.25 layer appears, which can enhance the ordering of A sites and oxygen vacancies, and the CP phase transforms into room-temperature ferromagnetic Sr0.8Er0.2CoO2.635 (OT, TC∼330 K). Er ions provide unpaired electrons in the 2f orbital, which results in a strong magnetization of Sr0.8Er0.2CoO2.635 (OT, 4.66 μB/Co) at low temperatures. [ABSTRACT FROM AUTHOR]

C40H48Cl2N4O9, monoclinic, C2 (no. 5), a = 13.434(2) Å, b = 7.2089(11) Å, c = 20.691(3) Å, β = 95.931(4)°, V = 1993.0(5) Å3, Z = 2, Rgt(F) = 0.0478, wRref (F2) = 0.1091, T = 173 K. [ABSTRACT FROM AUTHOR]

C21H16ClFeNO, monoclinic, P21/c (no. 14), a = 10.3273(5) Å, b = 23.0536(11) Å, c = 7.2835(4) Å, β = 106.078(2)°, V = 1666.24(15) Å3, Z = 4, Rgt(F) = 0.0558, wRref(F2) = 0.1219, T = 170 K. [ABSTRACT FROM AUTHOR]

• Intrinsic driving mechanisms of crystal nucleation induced by crystal structures and alloying under complex thermal stress are for the first time revealed. • Nucleation ability and growth rate in FCC, BCC, and HCP metals are compared. • Difference of constitutive supercooling caused by large thermal gradients and solute redistribution in various alloys are revealed. • Nucleation barrier free energy descends in order of FCC, BCC, and HCP when the complexity of the constituent elements of the metal is similar. The additive manufacturing (AM) technology has received the widespread attention in the industrial application because of its unique ability to achieve the complex shape and ideal performance. Unfortunately, the impact of the material natural characteristics, such as the crystal structure and alloying, on the microstructure formation at the nanoscale has never been revealed in AM metals. Here, we use large-scale molecular-dynamics simulations to study the rapid thermal deformation processes of additively-manufactured face-centered-cubic (FCC), body-centered-cubic (BCC), hexagonal close-packed (HCP) metals and their alloys (FCC Cu, CuAl 0.1 , BCC Fe, FeAl 0.1 , and HCP Mg, MgAl 0.1) in the molten pool, in an attempt to elucidate the intrinsic physical mechanisms controlling the crystal nucleation and growth under the complex thermal stress. The results show that the arcuate solid-liquid interface migrates towards the liquid phase until the complete crystallization, in good agreement with the experimental observation. The solidification rate follows a unified slow-to-fast law in the three types of metals, due to the competition between the compressive thermal stress and fast atomic motion. It is noteworthy that the critical radius of the crystal nucleus in the FCC and BCC metals is smaller than that in the HCP metal. The FCC metal exhibits the weak nucleation ability and growth rate, and yet the HCP metal shows the fast growth rate and stable columnar crystal nucleation. Especially, due to the dual regulation of the steep thermal gradient and solute redistribution on the growth driving force, the alloying increases the constitutive supercooling of the solidification front and inhibits the growth of columnar crystals. This trend is particularly prominent in FCC alloys, which is manifested by the obvious amorphous phase and discrete nucleation point in the upper part of the melt pool. The nucleation barrier free energy descends in order of FCC, BCC, and HCP pure metals, but the alloying would increase this energy in the corresponding alloys. The current work gives an insight into the atomic mechanism of the nucleation and growth in AM FCC, BCC, and HCP metals. [ABSTRACT FROM AUTHOR]

C25H37Cl2N5O6, triclinic, P 1 ‾ (no. 2), a = 8.115(4) Å, b = 8.656(4) Å, c = 22.641(9) Å, α = 81.344(9)°, β = 80.173(9)°, γ = 65.833(8)°, V = 1423.9(10) Å3, Z = 2, Rgt(F) = 0.0652, wRref(F2) = 0.2010, T = 173 K. [ABSTRACT FROM AUTHOR]

C20H20N2O2, monoclinic, P21 (no. 4), a = 8.3293(4) Å, b = 11.3947(5) Å, c = 8.9536(4) Å, β = 108.489(2)°, V = 805.92(6) Å3, Z = 2, Rgt(F) = 0.0495, wRref(F2) = 0.1094, T = 150 K. [ABSTRACT FROM AUTHOR]

C16H16FN3O, orthorhombic, Pbca (no. 61), a = 12.5936(10) Å, b = 7.7308(9) Å, c = 29.568(3) Å, V = 2878.7(5) Å3, Z = 8, Rgt(F) = 0.0872, wRref(F2) = 0.1893, T = 293 K. [ABSTRACT FROM AUTHOR]

C16H15ClN2O2, triclinic, P 1 ‾ (no. 2), a = 7.9715(8) Å, b = 8.2727(8) Å, c = 11.5105(12) Å, α = 90.296(8)°, β = 100.566(9)°, γ = 102.603(9)°, V = 727.41(13) Å3, Z = 2, Rgt(F) = 0.0522, wRref(F2) = 0.1257, T = 293 K. [ABSTRACT FROM AUTHOR]