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Cu2S crystallizes in the tetragonal P4_32_12 space group. The structure is three-dimensional. Cu1+ is bonded in a trigonal planar geometry to three equivalent S2- atoms. There are a spread of Cu–S bond distances ranging from 2.29–2.32 Å. S2- is bonded in a 6-coordinate geometry to six equivalent Cu1+ atoms.
Incorporating epitaxially grown active semiconductor media into self-assembled microsphere crystals has remained a major challenge as the curved geometry of the spheres is incompatible with conventional planar growth and patterning techniques. As a result, active photonic devices based on such self-assembled structures, which have other desirable properties such as enabling the rapid assembly of large area systems, have been elusive. Here, we numerically demonstrate an alternative route to creating high-Q resonances in microsphere-based nanophotonic assemblies compatible with standard optical gain materials. We show that close-packed layers of monodisperse microspheres can exhibit symmetry bandgaps, regardless of their layer stacking order. Thus, this microsphere environment can be used to create lines of bound states in the continuum (BICs) of an embedded slab made of active material. Using a realistic ZnS@SiO 2 (core-shell) architecture and sphere diameters compatible with scalable colloidal assembly, we predict sharp spectral features in angle-resolved transmission that trace these lines of BICs and persist in the presence of some fabrication disorder. Altogether, in enabling the integration of unpatterned epitaxial gain slabs with large-area colloidal microsphere assemblies, this approach opens a practical path toward active, dynamically reconfigurable photonic devices that leverage BIC physics for narrow-linewidth lasing and enhanced light–matter interactions.
LiFeSiO4 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Li1+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.93–1.96 Å. Fe3+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with four equivalent SiO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.86–1.91 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent FeO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Fe3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Fe3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Li1+, one Fe3+, and one Si4+ atom.
Herein, we report the discovery, structural and photophysical characterization of a new zero-dimensional (0D) lead-free all-inorganic halide, Rb 4 CuSb 2 Cl 11 , which adopts a new structure type. Single-crystal X-ray diffraction (SCXRD) shows that the structure consists of isolated, distorted seesaw [SbCl 4 ] − and trigonal planar [CuCl 3 ] 2− units, separated by Rb + cations that provide charge balance. Optoelectronic measurements and density functional theory (DFT) calculations indicate an indirect band gap of 2.89 eV, making it a candidate for wide-bandgap optoelectronic applications. Electrical resistivity was measured at 1.29 × 10 10 Ω·cm, and the trap-state density (n trap ) was found to be 7.44 × 10 10 cm −3 . Attempts to synthesize substitution analogs of Rb 4 CuSb 2 Cl 11 led to the synthesis of Rb 2 In 0.91(0.2) Sb 0.09 Cl 5 ·H 2 O, which was erroneously reported as Rb 2 SbCl 5 O in a previous study. Rb 2 In 0.91(0.2) Sb 0.09 Cl 5 ·H 2 O adopts a vacancyordered perovskite structure and exhibits broad-band yellow emission under UV excitation. The measured photoluminescence quantum yield (PLQY) for Rb 2 In 0.91 (0.2)Sb 0.09 Cl 5 ·H 2 O is 18.2%. These findings add to the growing class of quaternary metal halides with multiple cation and anion compositions, expanding the chemical phase space for the discovery of new materials with functional properties.
LuCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Lu3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Lu–B bond lengths are 2.85 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.08 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Lu3+ and six equivalent Co1+ atoms.
DyCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Dy3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Dy–B bond lengths are 2.88 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Dy3+ and six equivalent Co1+ atoms.
GdCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Gd3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Gd–B bond lengths are 2.90 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Gd3+ and six equivalent Co1+ atoms.
TbCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Tb–B bond lengths are 2.89 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Tb3+ and six equivalent Co1+ atoms.
YCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Y3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Y–B bond lengths are 2.90 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Y3+ and six equivalent Co1+ atoms.
HoCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Ho3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Ho–B bond lengths are 2.88 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Ho3+ and six equivalent Co1+ atoms.
ErCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Er3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Er–B bond lengths are 2.87 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.09 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Er3+ and six equivalent Co1+ atoms.
SmCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Sm3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Sm–B bond lengths are 2.92 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.10 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Sm3+ and six equivalent Co1+ atoms.
TmCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Tm–B bond lengths are 2.86 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.08 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Tm3+ and six equivalent Co1+ atoms.
LiAg2F6 crystallizes in the trigonal P321 space group. The structure is three-dimensional. Li1+ is bonded in a trigonal planar geometry to three equivalent F1- atoms. All Li–F bond lengths are 1.88 Å. Ag+2.50+ is bonded to six F1- atoms to form corner-sharing AgF6 octahedra. The corner-sharing octahedra tilt angles range from 44–46°. There are three shorter (2.12 Å) and three longer (2.18 Å) Ag–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two equivalent Ag+2.50+ atoms. In the second F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Ag+2.50+ atoms.
ZrCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Zr2+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Zr–B bond lengths are 2.81 Å. Co+1.33+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.07 Å. B3- is bonded in a 9-coordinate geometry to three equivalent Zr2+ and six equivalent Co+1.33+ atoms.
CeCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Ce3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Ce–B bond lengths are 2.91 Å. Co1+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.10 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Ce3+ and six equivalent Co1+ atoms.
ScCo3B2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Sc2+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Sc–B bond lengths are 2.82 Å. Co+1.33+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Co–B bond lengths are 2.05 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Sc2+ and six equivalent Co+1.33+ atoms.
CeIrAlH2 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ce is bonded in a hexagonal planar geometry to six equivalent H atoms. All Ce–H bond lengths are 2.55 Å. Ir is bonded to three equivalent Al and two equivalent H atoms to form corner-sharing IrAl3H2 trigonal bipyramids. All Ir–Al bond lengths are 2.52 Å. Both Ir–H bond lengths are 1.70 Å. Al is bonded in a trigonal planar geometry to three equivalent Ir atoms. H is bonded to three equivalent Ce and one Ir atom to form a mixture of edge and corner-sharing HCe3Ir trigonal pyramids.