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The Tibetan Plateau is characterized by the largest crustal thickness on Earth, although the timing of formation of the plateau remains debated. In this study, we present in situ laser ablation‐inductively coupled plasma‐mass spectrometry zircon U–Pb ages and Hf isotopes, and whole‐rock geochemical data on porphyritic granitoids of Sebuta in the central Lhasa block. Our zircon U–Pb data indicate that these rocks emplaced at ca. 89 Ma, in the early Late Cretaceous. Geochemically, the Sebuta biotite granite porphyry can be broadly divided into two subtypes, namely metaluminous porphyry and peraluminous porphyry. The metaluminous porphyry has high SiO2, Al2O3, Sr, low Y and Yb contents, and high Sr/Y and LaN/YbN ratios, showing adakitic features. These rocks have high K2O and Th contents, low Ti/Eu and Nd/Sm ratios, indicative of a continental crust affinity. Positive zircon εHf(t) values, along with high Mg#, Cr and Ni, imply that the Sebuta adakitic porphyry was most likely derived from partial melting of a delaminated thickened juvenile lower crust, and that the initial melts interacted with mantle peridotite during ascent. The field features, petrographic characteristics, formation age, ore‐bearing potential, and Hf isotope of the peraluminous porphyry are similar to those of the Sebuta adakitic porphyry, indicating that the peraluminous porphyry was likely formed by contamination with ancient crustal material and fractional crystallization from the same primary adakitic magmas which generated the Sebuta adakitic porphyry. Residual phases of amphibole + plagioclase + garnet + rutile in the source region, together with previous studies, suggest that the crust beneath the central‐northern Lhasa block experienced thickening during the early Late Cretaceous, and had already been thickened to more than 50 km by the Late Cretaceous (ca. 89 Ma). [ABSTRACT FROM AUTHOR]

Miocene postcollisional potassic and adakitic rocks are widely distributed in the southern Lhasa terrane and western central Lhasa terrane. However, coeval potassic and adakitic rocks in eastern central Lhasa terrane were rarely recognized, and their origins and formation mechanism remain controversial. In this paper, we provide new geochronological and geochemical data for the Miocene postcollisional potassic and adakitic intrusions exposed in the Qingdu area, eastern central Lhasa terrane, southern Tibet. The Qingdu Miocene intrusions consist of quartz monzonite porphyry and biotite granite with coeval zircon U–Pb ages of 14.1 Ma and 14.0 Ma, respectively. They have high SiO2 (67.98–75.32 wt.%), Al2O3 (14.13–14.78 wt.%), and K2O (4.06–6.18 wt.%) and low MgO (0.25–1.46 wt.%) contents. They are both enriched in light rare earth elements (LREEs) and depleted in heavy rare earth elements (HREEs), with high (La/Yb)N (25.37–42.32) ratios. The biotite granite samples have low Y (7.10–9.96 ppm) and Yb (0.61–0.85 ppm) contents, and high Sr (229–384 ppm) contents and high Sr/Y (30–41) ratios, which show adakitic geochemical characteristics, whereas the quartz monzonite porphyry samples show potassic geochemical characteristics. They display initial (87Sr/86Sr)i ratios of 0.7083–0.7103, εHf(t) values of −6.7 to −0.1, εNd(t) values of −8.96 to −7.44, (208Pb/204Pb)i ratios of 39.028–39.110, (207Pb/204Pb)i ratios of 15.662–15.684, and (206Pb/204Pb)i ratios of 18.541–18.577. These signatures indicate that both the potassic and adakitic intrusions are more likely to originate from partial melting of a thickened lower crust, which were mainly the products of the binary mixing between the juvenile and ancient crust components. Based on the spatial distributions and isotopic features of the postcollisional potassic and adakitic rocks in the Lhasa terrane, we suggest that the differences of the lower crustal composition played a crucial role in causing the geochemical variations of the Miocene postcollisional adakitic and potassic rocks in Lhasa terrane. [ABSTRACT FROM AUTHOR]

The Cuonadong Dome in southern Tibet is a newly discovered gneiss dome in the Tethys Himalaya. Here, we investigate the Late Cambrian augen gneiss (orthogneiss) within the core of this dome to address the controversy surrounding early Palaeozoic tectonic evolution of the northern margin of eastern Gondwana. We report new zircon laser ablation multicollector inductively coupled plasma mass spectrometry (LA‐(MC‐)ICP‐MS) U‐Pb ages, Lu‐Hf isotopes, whole‐rock major and trace element geochemistry, and Sr‐Nd‐Pb data on representative samples from the granitic gneiss. The weighted mean of 116 analyses of zircon grains yields an age of 498.2 ± 1.5 Ma (mean square weighted deviation [MSWD] = 1.2). Forty‐one spots analyses on these grains show consistent εHf (t) values of −2 to +4 (average = +1.1), corresponding to Hf crustal model age (TDM2) of 1.3 to 1.6 Ga (average = 1.39 Ga). The orthogneiss (metagranite) is characterized by high Si and K contents, with low Al, Mg, and Ti, and A/CNK values ranging from 0.87 to 0.98 with an average of 0.92, indicating a metaluminous composition and I‐type granitoid affinity. The granitoid displays significant enrichment in light rare earth elements (LREEs) and relatively flat high rare earth element (HREE) patterns, with strong negative Eu anomalies (Eu/Eu* = 0.26–0.31). The primitive mantle‐normalized trace elements show a relative enrichment in large‐ion lithophile elements, such as Rb, and high‐field strength elements, such as Th, U, Zr, and Hf, with depletion in Ba, Nb, Ta, Sr, P, and Ti. The rocks show high initial 87Sr/86Sr ratios (0.7221–0.7248) and low εNd (t) values (−8.9 to −7.3) with Nd model ages (TDM) of 1.79–1.91 Ga. Their radiogenic Pb isotopic compositions show (206Pb/204Pb)t = 18.804–19.110, (207Pb/204Pb)t = 15.730–15.768, and (208Pb/204Pb)t = 38.409–39.054, indicating an ancient upper middle continental crustal origin. Our study shows that the protolith of the metagranite was most likely derived from the partial melting of upper continental crust with a minor contribution of depleted mantle materials. Through integration of the regional information on early Palaeozoic magmatism and metamorphic events, we contend that the protolith of the Cuonadong granitic gneiss formed in an accretionary setting associated with the early Palaeozoic Proto‐Tethys Oceanic plate subduction beneath the Gondwana continent. [ABSTRACT FROM AUTHOR]

The white-light emission of a triple-component lanthanide coordination polymer turns to blue and red upon adding Mn2+ and Ag+ ions, respectively. [ABSTRACT FROM AUTHOR]

A series of new isostructural lanthanide(iii) complexes are reported which are constructed from Schiff base and β-diketonate ligands, namely, [Ln2(DBM)6(L)] (Ln = Sm (1), Eu (2), Gd (3), Dy (4), Yb (5); L = N,N′-bis(pyridin-2-ylmethylene)ethane-1,2-diamine, DBM = dibenzoylmethanide). The structures of the isomorphous complexes 1–5 were determined by single-crystal X-ray crystallography. The two Ln(iii) ions in the molecules of 1–5 are bridged by a Schiff base ligand that displays a curved configuration. Complexes 1, 2 and 5 exhibit lanthanide ion-based luminescence not only in the solid state but also in methanol solution. The lifetimes and quantum yields of luminescence were also determined. The magnetic analysis reveals that complexes 4 and 5 exhibit field-induced single-molecule magnet behavior with energy barriers (Ueff/kB) of 46.8 and 23.0 K at direct current fields of 2000 Oe, respectively. [ABSTRACT FROM AUTHOR]

Reactions of LnCl3·6H2O (Ln = La, Ce, Pr, Nd, Gd and Lu), l-dibenzoyl tartaric acid (l-DBTA) and triethylamine in a methanol–water solution afford four complexes 1a–4a with 1D ladder chain structures, e.g. {[Ln2(l-DBTA)3(CH3OH)x(H2O)y]·zH2O}n (x = 3 or 4, y = 3 or 4, z = 2 or 5; Ln = La (1a), Ce (2a), Pr (3a) and Nd (4a)) and two complexes 5 and 6 with 1D linear chain structures, e.g. {Et3NH[Ln(l-DBTA)2(CH3OH)2(H2O)2]·2H2O}n (Ln = Gd (5) and Lu (6)). Accidentally, an in situ irreversible SCSC transformation from the kinetically stabilized 1D ladder chain structures of 1a–4a to thermodynamically stabilized 1D linear chain structures of 1–4 was observed, which was seldom reported for lanthanide coordination polymers. The coordination stability around a lanthanide cation was investigated to expatiate on the irreversible SCSC transformation. The solid-state NIR luminescence for complexes 3a, 3, 4a and 4 was also studied. [ABSTRACT FROM AUTHOR]

The Bangong- Nujiang suture ( BNS) between the Lhasa and Qiangtang terranes is an important boundary and its petrogenesis is controversial. Diabase from the accretionary prism in the southern Qiangtang terrane yields a zircon U- Pb age of 181.3 ± 1.4 Ma. All the diabases show tholeiitic basalt compositions, gentle enrichment patters of light rare earth elements ( REE), variable enrichment in incompatible element concentrations (e.g. Th and Rb), and no anomaly in high field strength elements (e.g. Nb and Ta), similar to that of enriched mid-ocean ridge basalt ( E- MORB). They have relatively homogeneous whole rock Nd (ε Nd(t) = 7.3-9.1) and zircon Hf- O isotopic compositions (ε Hf(t) = 14.8-16.1, and δ18 O = 4.57-6.12‰), possibly indicating melting of the depleted mantle and no significant crustal contamination during the petrogenesis. The element variations suggest that the diabases were formed by plume-ridge interaction at a mid-ocean ridge within the Bangong- Nujiang ocean. [ABSTRACT FROM AUTHOR]

A series of novel organic–inorganic complexes based on trivalent lanthanides and 1,3-C6H4[CH2P(O)(OH)2]2 (H4L) formulated as Ln(HL)(H2O)2 (Ln = La, 1; Pr, 2; Nd, 3; Sm, 4; Eu, 5; Gd, 6; and Tb, 7) have been obtained as single phases by regulating the pH under hydrothermal conditions. Complexes are isostructural and feature a network in which the LnO7 polyhedra are interconnected by bridging CPO3 tetrahedra into inorganic layers. These layers are further stacked with the benzyl groups of ligands via C–H…π interaction into a laminar framework architecture. Luminescent measurements indicate that complexes 4, 5 and 7 show strong metal-centered emission bands in yellow, red and green light regions, respectively. Magnetic properties of 2 and 7 have also been studied. [ABSTRACT FROM AUTHOR]

Two type lanthanide complexes obtained by salen-type ligand N,N'-ethylenebis(salicylideneimine) (HL) and N,N'-ethylene-bis(3-methoxysalicylideneimine) (HL) have been isolated. They are 2D coordination polymer [Yb(HL)(NO)] ( 1), mononuclear Ln(HL)(NO) [Ln = Sm ( 2), Ho ( 3)]. The structures of 1- 3 were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. [ABSTRACT FROM AUTHOR]

Three dinuclear lanthanide complexes are achieved by using H2salen or H2salen/acac ligands (H2salen = N,N′-ethylenebis(salicylideneimine), acac = acetylacetonate). They are homodinuclear [Er2(salen)3] (1), [Yb2(salen)2(acac)2] (2), and heterodinuclear geometrical [ErYb(salen)2(acac)2] (3). The structures of complexes were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. The homonuclear Yb2 complex exhibits characteristic metal-centered NIR emission. The geometric ErYb isomer exhibits ‘dual emissions’ from both erbium(iii) and ytterbium(iii) ions. There was no detectable photoluminescence in the Er2 complex, not only in solid state but also in solvent. [ABSTRACT FROM AUTHOR]

Abstract: A biphenyl-linked bis-β-diketone ligand, 3,3′-bis(3-phenyl-3-oxopropanol)biphenyl (BPB) has been prepared for the syntheses of a series of dinuclear lanthanide complexes. The ligand bears two benzoyl β-diketonate sites linked by a 3,3’-biphenyl spacer. Reaction of the doubly negatively charged bis-bidenate ligand with lanthanide ions forms triple-stranded dinuclear complexes Ln2(BPB)3 (Ln=Nd (1), Sm (2), Eu (3), Yb (4) and Gd (5)). Electrospray mass spectrometry is used to identify the formation of the triple-stranded dinuclear complexes 1–5, which have been further characterized by various spectroscopic techniques. The complexes display strong visible and NIR luminescence upon excitation at ligands bands around 360nm, depending on the choice of the lanthanides, and the emission quantum yields and luminescence lifetimes of 2–3 have been determined. It shows that the biphenyl-linked ligand BPB is a more efficient sensitizer than the monodiketone ligand DBM (dibenzoylmethane), through the comparisons of Ln2(BPB)3 and Ln(DBM)3 on their photoluminescent properties. [Copyright &y& Elsevier]

Abstract: Three novel N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane dimeric lanthanide complexes, namely, [{H2L}Sm(NO3)3]2·H2O (1), [{H2L}Gd(NO3)3]4·CH3OH (2), [{H2L}Lu(NO3)3]4·H2O (3) (H2L= N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) and three new N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane 3d-Gd heterodinuclear complexes, namely, [{LCo}(CH3COO)(CH3COOH)Gd(NO3)2] (4), [{LNi(MeOH)2}Gd(NO3)3]·2MeOH (5) and [{(L)Zn(HNO3)}Gd(NO3)3]·NO3·H3O·MeOH (6) have been synthesized and isolated. X-ray crystallographical analysis reveals that complexes 1–3 are isomorphic with unique dimeric topology. Complexes 4–6 are of discrete 3d–4f dinuclear cores. Magnetic properties of complexes 2 and 4–6 are systematically investigated. Complexes 4 and 5 are ferromagnetic, while 2 and 6 are antiferromagnetic. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of Ln(NO3)3·6H2O with H2L [H2L=N,N′-bis(salicylidene)propane-1,2-diamine] gives rise to five new coordination polymers, viz. [Pr(H2L)(NO3)3(MeOH)] n (1) and [Ln(H2L)1.5(NO3)3] n [Ln=La (2), Eu (3), Sm (4) and Gd (5)]. Crystal structural analysis reveals that H2L effectively functions as a bridging ligand forming one-dimensional (1D) chain and two-dimensional (2D) open-framework polymers. Solid-state fluorescence spectra of 3 and 4 exhibit typical red fluorescence of Eu(III) and Sm(III) ions at room temperature while 2 emits blue fluorescence of ligand H2L. The lowest triplet level of ligand H2L was calculated on the basis of the phosphorescence spectrum of 5. The energy transfer mechanisms in the lanthanide polymers were described and discussed. [Copyright &y& Elsevier]

Abstract: Lewis acid/base addition between Ln(NO3)3 ·6H2O (Ln=Pr, Nd, Sm, Eu, Tb and Lu) and H2salen [H2salen= N,N′-ethylenebis(salicylideneimine)] gives rise to an array of coordination polymeric structures. Crystal structural analysis reveals that Salen effectively functions as a bridging ligand in these compounds. The size of the lanthanide ions controls the structures of these Salen lanthanide complexes. Two representative structures with one dimensional and two dimensional topologies, viz. [Pr(H2salen)(NO3)3(CH3OH)2] n (1) and [Ln(H2salen)1.5(NO3)3] n [Ln=Pr (2), Nd (3), Sm (4), Eu (5), Tb (6) and Lu (7)] are reported. Luminescent spectra of complexes 4 and 5 exhibit characteristic metal-centered emission lines. However, the characteristic luminescence of the terbium(III) ion is not observed either in solution or in the solid state of complex 6. [Copyright &y& Elsevier]

(a) CL image of Sch3 grains consisting of a homogeneous core and several growth zones. Note that the Zone D and D′ exhibit dissolved inner margins (designated by arrow); (b) REE patterns from the imaged grain. Location of analyses in the domain of the images are marked by the same symbols as in the chondrite normalized REE diagrams; (c, d) CL images and EMPA maps of uranium in scheelite. Location of the mapping domain are marked on (a). • Three generations of scheelite were identified at Dabaoshan deposit. • From early to late generations, scheelites are gradually depleted in Mo, Nb, Ta, V, but enriched in U, Th. • The CL intensity of scheelite shows a negative correlation with U concentrations. • Trace elements and REE in scheelite record the evolution of ore-forming fluids at Dabaoshan deposit. Scheelite, a good proxy to record the complex history of hydrothermal evolution, has been investigated in the Dabaoshan porphyry Mo-W deposit, South China. Based on cathodoluminescence (CL) textures, mineral paragenesis, and chemical characterization, three generations of scheelite were identified (Sch1–Sch3). Sch1 is disseminated in porphyry rocks, or occasionally occurs in early quartz-molybdenite veins. It is CL-dark and contains high concentrations of V, Sr, Mo, Nb, Ta, and rare earth elements (REE), low U/Th ratios (0.37 mean) and light REE (LREE)-enriched patterns with negative Eu anomalies. Sch2 and Sch3 mainly occur in late quartz-pyrite-scheelite ± chalcopyrite veins. Sch2 is CL-bright and commonly rims Sch1, and/or is overgrown by late oscillatory Sch3. Compared with Sch1, Sch2 shows depletion in V, Sr, Mo, Nb, and Ta, but slight enrichment in U and Th, and is characterized by middle REE (MREE)-enriched patterns with negative Eu anomalies. Sch3 grains show reddish-brown color under transmitted light and exhibit oscillatory zonation under CL. Sch3 has elevated concentrations of Mn, U (up to 4484 ppm), and Th (up to 18.8 ppm) contents, and high U/Th ratios (1175 mean). Chemical mapping reveals a negative correlation between U concentrations and CL intensity, which is attributed to the radiation damage caused by the radioactive decay of U. Based on the REE patterns, Sch3 is subdivided into Sch3a and Sch3b. Sch3a shows MREE-enriched patterns with slight negative to positive Eu anomalies, while Sch3b is LREE-enriched and shows gradual depletion in MREE and HREE with increasing positive Eu anomalies in consecutive growth zones. The Dabaoshan porphyry and all generations of scheelites show similar Y/Ho ratios, indicating that ore-forming fluids were mainly derived from the Dabaoshan porphyry. Our results reveal that REE chiefly substitute into scheelite by the mechanism Ca2+ = REE3+ + Na+ while U substitutes for W into scheelite. Sch1 containing the highest concentrations of Mo, V, Nb, and Ta precipitates from the magmatic fluids at high temperature. It inherits the LREE-enriched patterns and negative Eu anomalies from the causative porphyry. From early to late generations, the gradual depletion of Mo, Nb, Ta, and V in scheelite is ascribed to the precipitation of molybdenite, rutile, and scheelite, whereas the increasing concentrations of U and Th in scheelite indicates the gradual enrichment of U and Th in ore-forming fluids. The increasing U/Th ratios in scheelites may result from not only the differential solubility between U and Th in fluids, but also the preferential incorporation of U relative to Th in scheelite. Compared with Sch1, Sch2 and Sch3a are depleted in LREE, which is interpreted to reflect the precipitation of apatite. Sch3b with various REE patterns within single grains is interpreted as precipitation from a closed-system accompanied by intermittent fluid replenishment. This study demonstrates that REE patterns of scheelite are controlled by multiple factors, including substitution mechanism, fluid composition, hydrothermal alteration, precipitation of REE-rich minerals, and hydrothermal dynamics during scheelite growth. The systematic variation of trace elements in scheelite suggests that scheelite chemistry can be used to monitor the evolution of ore-forming fluids in the Dabaoshan deposit. [ABSTRACT FROM AUTHOR]

As prototypes of crust-derived remelted S-type granite, Himalayan leucogranites have considerable relevance in crustal evolution and associated metallogeny. However, given their highly differentiated character, the petrogenesis of these rocks has remained controversial. This study reviews the geochemical and isotopic data from >2000 samples of Himalayan Cenozoic granitoids to evaluate their genesis. The Himalayan leucogranites include two major belts: the northern zone occurs in the Tethyan Himalayas and gneiss domes, and the southern zone is exposed mainly at the top of the Higher Himalayas. The ages of these rocks show a southward younging trend from 49 Ma to 1 Ma. The main rock types are two-mica granites and garnet-tourmaline-bearing muscovite granites, whereas Eocene and Miocene intermediate-mafic and adakitic rocks are developed mainly in the northern belt. The leucogranites originated from incongruent disequilibrium partial melting of the Greater Himalayan Crystalline Complex and underwent a high degree of differentiation and fractional crystallization. The rocks are strongly peraluminous and characterized by high Si, K, and Na; low Ca, Fe, Mg, Ti, and Mn; and low rare earth elements with obvious tetrad effects and negative Eu anomalies. A more striking feature of these granites is their high Rb/Sr and Y/Ho values and low Th/U, Nb/Ta, Zr/Hf, and K/Rb values. The Sr–Nd–Pb–Hf isotopes indicate that the proportion of older crustal material in the magmatic source area gradually increased from the Eocene to the Pliocene. The Cenozoic magmatic activity can be divided into five stages—49-40 Ma, 39–29 Ma, 28–15 Ma, 14–7 Ma, and 6–0.7 Ma—and their geotectonic settings are related to the break-off of the Neo-Tethyan oceanic plate, low-angle underthrusting of the Indian continental lithosphere, break-off or rollback of the Indian plate, tearing of the Indian lithospheric slab or delamination of the lithospheric mantle, and rapid extrusion and uplift of the Eastern and Western Himalayan Syntaxis resulting from flat subduction of the Indian continent, respectively. Stream sediment geochemical data from previous work show high positive anomalies for some rare metals in the Himalayas. The average contents of Li, Be, Sn, Ta and Cs in pegmatite are 2466 ppm, 93 ppm, 29 ppm, 14 ppm and 61 ppm, respectively. All these elements have enrichment coefficients higher than 10 compared to the upper continental crust. Recent progress in ore prospecting shows that the Himalayan Cenozoic leucogranite is emerging as a new world-class rare metal metallogenic belt. [Display omitted] • First comprehensive review of the world-famous Himalayan leucogranites. • The leucogranites originated from partial melting of GHC. • They underwent a high degree of differentiation and fractional crystallization. • They cover five stages: 49–40 Ma, 39–29 Ma, 28–15 Ma, 14–7 Ma, and 6–0.7 Ma. • The Himalayas are emerging as a new world-class rare metal metallogenic belt. [ABSTRACT FROM AUTHOR]

Twoseries of lanthanide–organic frameworks with the formulas[Ln(BTATB)(DMF)2(H2O)]·DMF·2H2O (Ln = La (1a), Eu (2a), Tb (3a), Er (4a)) and [Ln(BTATB)(H2O)2]·2DMA·4H2O (Ln = Er (1b), Yb (2b), Lu (3b)), respectively, weresolvothermally synthesized from 4,4′,4″-(benzene-1,3,5-triyltris(azanediyl))tribenzoate(H3BTATB) and Ln(NO3)3under DMFor DMA media and characterized by thermogravimetric analyses, IR spectroscopy,X-ray powder diffraction, and single crystal X-ray diffraction. X-raysingle-crystal diffraction analyses for these complexes revealed thatseries A features an interesting 2D interdigitated layer architecturewith (6,3) topology. Series B exhibits a 2D bilayer structure. Theluminescence properties were studied, and the results showed thatcomplex 3adisplayed strong fluorescent emission in thevisible region, where the emission intensities of 3aareenhanced upon the addition of Zn2+, demonstrating Zn2+-modulated fluorescence. Yb(III) complex 2bemitstypical near-infrared luminescence (983 nm) in DMF (λex= 315 nm). The Knoevenagel condensation reaction (benzaldehyde andmalononitrile or ethyl cyanoacetate in acetonitrile) was studied using 3aand 2bas catalysts. The results showed thatthe conversion rates of reactions catalyzed by 3aincreasedto 99 and 42%, respectively, whereas the reactions catalyzed by 2bexhibited lower conversion rates. [ABSTRACT FROM AUTHOR]

Highlights: [•] Seven lanthanide TCNQ complexes were obtained. [•] The reaction solvent has an important effect on the structures of complexes. [•] The magnetic and electrochemical properties of complexes were investigated. [ABSTRACT FROM AUTHOR]

A seriesof novel organic–inorganic complexes based on trivalentlanthanide and HOOC–C6H4–CH2PO(OH)(OC2H5) (H2L′)formulated as Ln(HL)(H2L)(H2O) (H3L= HOOC–C6H4–CH2PO(OH)2, Ln= La, 1; Ce, 2; Pr, 3; Nd, 4; Sm, 5; Eu, 6; Gd, 7; and Tb, 8) have been obtained as single phases byregulating the pH values under hydrothermal conditions. They are isomorphousand feature a network in which the LnO7polyhedra are interconnectedby bridging CPO3tetrahedra into inorganic layers. Theselayers are further cross-linked by hydrogen bonds of the carboxylacid groups of ligands into a S-shape pillared framework architecture.Luminescent measurements indicate that complexes 1–5and 7exhibit ligand-centered blue light emissionbands. Complexes 6and 8display Ln-centeredstrong red and green luminescence, respectively. To elucidate theenergy transfer process between ligands and metal ions, the energylevels of the relevant electronic states have been estimated. SimultaneouslyEu3+and Tb3+were observed to accept energywith their several different 5Dj, resonance levels depending on the lowest triplet state energy levelof the ligand. Magnetic properties of 7and 8have also been studied. [ABSTRACT FROM AUTHOR]

Twoseries of eight polycarboxylate lanthanide coordination complexes,namely, [Ln(cpia)(H2O)2]·4H2O {Ln = Ce (1), Nd (2), and Sm (3)} and [Ln(cpia)(H2O)n]2·2H2O {Ln = Eu (4), Gd (5), Tb (6), Er (7),and Lu (8), n= 5 in 4–7; n= 4 in 8} {H3cpia = N-[4-(carboxymethoxy)phenyl]iminodiaceticacid}, have been synthesized by self-assembly and characterized byIR, thermogravimetric analysis, and X-ray crystallography. Complexes 1–3are isomorphic featuring two-dimensionaldouble layer structures, while the isomorphic complexes 4–8exhibit [2 + 2] rectangle metallomacrocyclestructures. Further, photoluminescence (PL) spectra of complexes 2, 4, and 6show the strong characteristicluminescence of Eu(III), Tb(III), and Nd(III) ions, respectively,suggesting that cpia3–is able to efficiently sensitizethe luminescence of lanthanide ions. [ABSTRACT FROM AUTHOR]

The appinite suite of rocks offers a unique opportunity to reveal the properties of subarc lithospheric mantle, indicate essential crust-mantle interactions, and ascertain critical geodynamic settings. In this study, we present zircon U–Pb ages, Hf–O isotopes, and whole-rock geochemical data for the newly identified Duobaoshan appinite-granite suite in the eastern Central Asian Orogenic Belt (CAOB). Field and petrographic investigations show that this suite of rocks is composed of hornblende gabbro, quartz monzonite, and granite porphyry. The appinites are abnormally hornblende-rich, and contain spectacular hornblende phenocrysts, pegmatitic textures, and miarolitic cavity structures that indicate an anomalous water-rich origin. The quartz monzonite and granite porphyry show intrusive contact relations with the appinites. Secondary ion mass spectrometry (SIMS) zircon dating reveals that the Duobaoshan appinite-granite suite was emplaced in a very short time interval of 224–223 Ma. These samples show typical subduction related arc magmatic geochemical characteristics that are enriched in large-ion lithophile elements (LILEs) and light rare earth elements (REEs), depleted in high field strength elements (HFSEs) and middle and heavy REEs. All samples exhibit comparative total REEs and no significant evolutionary relationships. The appinites show high Sr/Y ratios (reaching ~100) and positive or zero Eu anomalies, which reveal amphibole fractionation promotion and plagioclase fractionation suppression in a water-rich magma system. The quartz monzonite possesses high Sr/Y and La/Yb ratios that exhibit adakite-like properties and were derived from thickened lower continental crust. The granite porphyry is silica-rich and non-adakitic. All samples have juvenile whole-rock initial 87Sr/86Sr ratios (~0.7038) and ɛ Nd (t) values. Zircons have depleted mantle-like ɛ Hf (t) (to +12.0) and δ18O (~ + 5.65‰) values. Combining these geochemical features with observations of the regional geology and tectonic setting, we propose that the Duobaoshan appinite-granite suite was generated under a Triassic back-arc extensional setting related to the southward subduction of the Mongol-Okhotsk Ocean. The appinites were derived from an unusual water-rich mantle source, which was previously metasomatized by slab-derived fluids. The quartz monzonite and granite porphyry were generated from partial melting of the juvenile lower continental crust triggered by coeval appinitic magma underplating. [Display omitted] • The Triassic Duobaoshan appinite-granite suite was emplaced ca. 224–223 Ma. • The mafic appinites were derived from an unusual water-rich mantle source. • Appinitic magma underplating causes juvenile crust melt and formation of granitoids. • Appinite-granite suite generated in an extensional setting of Mongol-Okhotsk Ocean. [ABSTRACT FROM AUTHOR]