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Nd(OH)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Nd3+ is bonded in a 9-coordinate geometry to nine equivalent O2- atoms. There are three shorter (2.52 Å) and six longer (2.54 Å) Nd–O bond lengths. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. O2- is bonded in a single-bond geometry to three equivalent Nd3+ and one H1+ atom.
Nd(OH)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Nd3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Nd–O bond distances ranging from 2.52–2.57 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to three equivalent Nd3+ and one H1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to three equivalent Nd3+ and one H1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to three equivalent Nd3+ and one H1+ atom.
Reported here is the synthesis, crystal structure, and solid-state characterization of a new americium containing metal–organic framework (MOF), [Am(C 9 H 3 O 6 )(H 2 O)], MOF-76(Am). This material is constructed from Am 3+ metal centers and 1,3,5-tricarboxylic acid (BTC) ligands, forming a porous three-dimensional framework that is isostructural with several known trivalent lanthanide (Ln) analogs (e.g., Ce, Nd, and Sm–Lu). The Am 3+ ions have seven coordinates and assume a distorted, capped trigonal prismatic geometry with C1 symmetry. The Am 3+ –O bonds were studied via infrared spectroscopy and compared to several MOF-76(Ln) analogs, where Ln = Nd 3+ , Eu 3+ , Tb 3+ , and Ho 3+ . The results show that the strength of the ligand carboxylate stretching and bending modes increase with Nd 3+ < Eu 3+ < Am 3+ < Tb 3+ < Ho 3+ , suggesting the metal–oxygen bonds are predominantly ionic. Optical absorbance spectroscopy measurements reveal strong f–f transitions; some exhibit pronounced crystal field splitting. The photoluminescence spectrum contains weak Am 3+ -based emission that is achieved through direct and indirect metal center excitation. The weak emissive behavior is somewhat surprising given that ligand-to-metal resonance energy transfer is efficient in the isoelectronic Eu 3+ (4f 6 ) and related Tb 3+ (4f 8 ) analogs. The optical properties were explored further within a series of heterometallic MOF-76(Tb 1–x Am x ) (x = 0.8, 0.2, and 0.1) samples, and the results reveal enhanced Am 3+ photoluminescence.
In this study, single crystals of RE 3 Ni 5 Al 19 series (RE = Y, Nd, Sm, Gd, Tb, Dy, Ho, and Er) are grown using the Al self-flux method. The crystal structure is examined by both single crystal and powder X-ray diffraction. Physical properties are studied for the first time for RE 3 Ni 5 Al 19 (RE = Y, Nd, Gd, Tb, Dy, Ho, and Er) by means of magnetic susceptibility, electrical resistivity, and heat capacity measurements. Complex magnetic behaviors, with up to three transitions present for RE = Sm, Gd, Tb, and Dy, are revealed. Y 3 Ni 5 Al 19 is found to be a nonmagnetic nonsuperconducting metal (above T = 1.8 K) with weak electron–phonon coupling strength.
The challenge of growing rare-earth (RE) sesquioxide crystals can be overcome by tailoring their structural stability and melting point via composition engineering. This work contributes to the advancement of the field of crystal growth of high-entropy oxides. A compound with only small REs (Lu,Y,Ho,Yb,Er) 2 O 3 maintains a cubic C-type structure upon cooling from the melt, as observed via in-situ high-temperature neutron diffraction on aerodynamically levitated samples. On the other hand, a compound with a mixture of small and large REs (Lu,Y,Ho,Nd,La) 2 O 3 crystallizes as a mixture of a primary C-type phase with an unstable secondary phase. Crystals of compositions (Lu,Y,Ho,Nd,La) 2 O 3 and (Lu,Y,Gd,Nd,La) 2 O 3 were grown by the micro-pulling-down (mPD) method with a single monoclinic B-type phase, while a powder of (Lu,Y,Ho,Yb,Er) 2 O 3 did not melt at the maximum operating temperature of an iridium-rhenium crucible. The minimization of the melting point of the two grown crystals is attributed to the mismatch in cation sizes. The electron probe microanalysis reveals that the general element segregation behavior in the crystals depends on the composition.
A summary is presented of the spectroscopic study of three systems: LaF3:Ho(3+), LaF3:Er(3+) and CaF2:Nd(3+). When the D levels of Ho(3+) in LaF3 were resonantly excited with a laser beam of 640 nm, upconverted emissions were detected from J (416 nm), F (485 nm), and E (546 nm) levels. Energy upconverted emissions were also observed from F and E levels of Ho(3+) when the material was excited with an 800 nm near infrared laser. When the D levels of Er(3+) in LaF3 were resonantly excited with a laser beam of 637 nm, upconverted emissions were detected from the E (540 nm) and P (320, 400, and 468 nm) levels. Energy upconverted emissions were also observed from F, E, and D levels of Er(3+) when the material was resonantly excited with an 804 nm near infrared laser. When the D levels of Nd(3+) in CaF2 were resonantly excited with a laser beam of 577 nm, upconverted emissions were detected from the L (360 and 382 nm), K (418 nm), and I (432 nm) levels. Very weak upconverted emissions were detected when this system was irradiated with a near infrared laser. The numbers in parentheses are the wavelengths of the emissions.
High-entropy rare-earth (RE) sesquioxides (RE 2 O 3 ) containing five cations in equimolar amounts have been investigated for a variety of applications, but little is known about their polymorphic behavior and coefficient of thermal expansion. Here, in this work, we evaluate the effect of the average ionic radius (AIR) on the polymorphism of high-entropy RE 2 O 3 . Powder samples of compositions 1 (Lu,Y,Ho,Nd,La) 2 O 3 (AIR = 0.938 Å) and 2 (Gd,Eu,Sm,Nd,La) 2 O 3 (AIR = 0.982 Å) were synthesized via a wet chemical method, and bead samples were prepared for aerodynamic levitation by melting the powders in a copper hearth. Structural transitions were monitored upon cooling from the melt to 1000 °C via in situ X-ray diffraction on aerodynamically levitated samples. The phase evolution was liquid, hexagonal H-type, and monoclinic B-type for composition 1 and liquid, cubic X-type, H-type, and B-type for composition 2. Based on their AIR, the general polymorphic transformations of the high-entropy RE 2 O 3 follow the trend of single-RE RE 2 O 3 , but the transition temperatures differ from those of single-RE RE 2 O 3 . The coefficient of thermal expansion values of the B-type phase of compositions 1 and 2 are similar to those of Gd 2 O 3 and previously published high-entropy RE 2 O 3 .
Frustrated lanthanide oxides are promising candidates for cryogen-free magnetic refrigeration due to their suppressed ordering temperatures and high magnetic moments. While much attention has been paid to the garnet and pyrochlore lattices, the magnetocaloric effect in frustrated face-centered cubic (fcc) lattices remains relatively unexplored. We previously showed that the frustrated fcc double perovskite Ba 2 GdSbO 6 is a top-performing magnetocaloric material (per mol Gd) because of its small nearest-neighbor interaction between spins. Here we investigate different tuning parameters to maximize the magnetocaloric effect in the family of fcc lanthanide oxides, A 2 LnSbO 6 (A = {Ba 2+ , Sr 2+ } and Ln = {Nd 3+ , Tb 3+ , Gd 3+ , Ho 3+ , Dy 3+ , Er 3+ }), including chemical pressure via the A site cation and the magnetic ground state via the lanthanide ion. Bulk magnetic measurements indicate a possible trend between magnetic short-range fluctuations and the field-temperature phase space of the magnetocaloric effect, determined by whether an ion is a Kramers or a non-Kramers ion. We report for the first time on the synthesis and magnetic characterization of the Ca 2 LnSbO 6 series with tunable site disorder that can be used to control the deviations from Curie–Weiss behavior. Taken together, these results suggest fcc lanthanide oxides as tunable systems for magnetocaloric design.
Experimental and computational analyses of [M(pdtz) 3 (H 2 O) 3 ]·3.5H 2 O (M 3+ = Pu 3+ −Cm 3+ , La 3+ −Nd 3+ , and Sm 3+ −Ho 3+ , pdtz− = 5-(2-pyridyl)-1H-tetrazolate) were conducted to understand potential differences in bonding between lanthanide and actinide complexes with a N-donor ligand. Structural analyses show that the An−N bond distances in the Pu 3+ , Am 3+ , and Cm 3+ complexes are within error of one another. Whereas in the lanthanide series, there is a nearly linear decrease in the Ln−N bond lengths from La 3+ to Ho 3+ (excluding Pm 3+ ). The An−N bond lengths are ∼0.015 Å shorter than their similarly-sized lanthanide analogs, in agreement with computational results that suggest greater covalent character in these bonds versus those with lanthanides. QTAIM analysis indicates that the An−N orbital mixing remains essentially unchanged from Pu 3+ to Cm 3+ , consistent with the nearly identical An−N bond lengths. However, upon deconvolution of the NLMOs into orbital compositions, the metal orbital contributions to An−N bonding decreases slightly overall wherein the 6d involvement remains constant, 7s involvement slightly increases, and 5f participation decreases. The molecular orbital energy diagram indicates that energy degeneracy between the 5f metal and 2p ligand orbitals increases from Pu 3+ to Cm 3+ and counteracts the contraction of the 5f orbtials. Together with prior reports of decreasing energy degeneracy between 5f and 3p orbitals from Np 3+ to Cf 3+ , these observations provide guidance on understanding how chemical bonding evolves in the actinide series.
Our recent observations of an unexpected Ce(III) hydrolysis product from the reaction of 4-amino-1,2,4-triazole (4-NH 2 -1,2,4-Triaz) with CeCl 3 ·7H 2 O, [Ce 6 (μ 3 -O) 4 (μ 3 -OH) 2 (μ 3 -Cl) 2 (Cl) 6 (μ 2 -4-NH 2 -1,2,4-Triaz) 12 ]·7H 2 O, the first high-nuclearity lanthanide complex where all Ln atoms are connected pairwise through 12 N-donor ligands or 12 neutral bridging ligands of any type, prompted us to explore the utility of this ligand in trapping additional f-element examples. Reactions of LnCl 3 ·6H 2 O (Ln = Nd, Eu, Ho) with a large excess of 4-NH 2 -1,2,4-Triaz (20 equiv) and with the addition of small amounts of water to help solubilize the metal salts led to the isolation of the unique hydrolysis products [Nd 6 (μ 3 -OH) 8 Cl 6 (μ 2 -4-NH 2 -1,2,4-Triaz) 12 ][Cl 4 ]·2H 2 O, [Eu 6 (μ 6 -Cl) 0.23 (μ 3 -O 0.77 ) 4 (μ 3 -O) 2.6 (μ 3 -Cl) 0.4 Cl 6 (μ 2 -4-NH 2 -1,2,4-Triaz) 12 ], and [Ho 6 (μ 6 -Cl) 0.21 (μ 3 -O 0.79 ) 4 (μ 3 -OH) 2 Cl 6 (μ 2 -4-NH 2 -1,2,4-Triaz) 12 ][Cl] 3.4 . Here, we also report a Ce(III) analogue prepared in glassware contaminated with Pb(OAc) 2 , namely, [Ce 6 (μ 3 -OH) 8 (BrPbBr 5 )(μ 2 -4-NH 2 -1,2,4-Triaz) 11.5 (OH 2 ) 6 ][Pb 0.84 Br 4.2 ][Br] 3.8 ·2(4-NH 2 -1,2,4-Triaz)·3.6H 2 O. The Nd(III) complex is the structurally most ordered with a clear [Nd 6 (μ 3 -OH) 8 ] cluster core, while the Eu(III) and Ho(III) compounds contain partial occupancy of a μ 6 position and thus result in an incomplete Ln 6 O 9 cluster core formation. The crystallographic results suggest that the 4-NH 2 -1,2,4-Triaz ligand brings Ln(III) ions together, followed by the formation of an Ln 6 O 8 or Ln 6 O 9 core with whatever remaining anions or ligands can be incorporated. Given the complexity of the hydrolysis products of nuclear waste, we expect to continue to find a myriad of closely related complex structures of these types for the f-elements.
Nd(HoS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with three HoS6 octahedra, edges with two equivalent HoS6 octahedra, and edges with four equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Ho–S bond distances ranging from 2.69–2.92 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, a cornercorner with one HoS7 pentagonal bipyramid, edges with four equivalent HoS6 octahedra, and edges with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Ho–S bond distances ranging from 2.66–2.77 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, and edges with four equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Ho–S bond distances ranging from 2.65–2.78 Å. Nd3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.89–3.03 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Ho3+ atoms. In the second S2- site, S2- is bonded to three Ho3+ and one Nd3+ atom to form distorted SNdHo3 trigonal pyramids that share corners with two equivalent SNd2Ho3 square pyramids, corners with four SNd2Ho3 trigonal bipyramids, corners with four SNdHo3 trigonal pyramids, edges with three equivalent SNd2Ho3 square pyramids, and edges with two equivalent SNd3Ho2 trigonal bipyramids. In the third S2- site, S2- is bonded to four Ho3+ atoms to form distorted SHo4 trigonal pyramids that share corners with three equivalent SNd2Ho3 square pyramids, corners with four equivalent SNd2Ho3 trigonal bipyramids, corners with four SNdHo3 trigonal pyramids, an edgeedge with one SNd2Ho3 trigonal bipyramid, and edges with two equivalent SHo4 trigonal pyramids. In the fourth S2- site, S2- is bonded to three equivalent Ho3+ and two equivalent Nd3+ atoms to form distorted SNd2Ho3 square pyramids that share corners with six SNd2Ho3 trigonal bipyramids, corners with five SNdHo3 trigonal pyramids, edges with four equivalent SNd2Ho3 square pyramids, edges with two SNd2Ho3 trigonal bipyramids, and edges with three equivalent SNdHo3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent Nd3+ atoms to form distorted SNd2Ho3 trigonal bipyramids that share corners with two equivalent SNd2Ho3 square pyramids, corners with two equivalent SNd3Ho2 trigonal bipyramids, corners with seven SNdHo3 trigonal pyramids, an edgeedge with one SNd2Ho3 square pyramid, edges with five SNd2Ho3 trigonal bipyramids, and an edgeedge with one SHo4 trigonal pyramid. In the sixth S2- site, S2- is bonded to two equivalent Ho3+ and three equivalent Nd3+ atoms to form distorted SNd3Ho2 trigonal bipyramids that share corners with four equivalent SNd2Ho3 square pyramids, corners with two equivalent SNd2Ho3 trigonal bipyramids, a cornercorner with one SNdHo3 trigonal pyramid, an edgeedge with one SNd2Ho3 square pyramid, edges with seven SNd2Ho3 trigonal bipyramids, and edges with two equivalent SNdHo3 trigonal pyramids.
Praseodymium nickelate, Pr 2 NiO 4 (PNO), is a promising electrode to promote oxygen reduction reaction (ORR) in a solid oxide fuel cell, but it exhibits phase transformation during electrochemical operation. The origin of the simultaneous phase transformation and high electrochemical performance remains obscure. We carried out a systematic density functional theory study to elucidate the mechanism for this conjugated phenomenon. Charge, electronic structure, and normal-mode analysis suggest the presence of peroxide. Our study shows that the formation of peroxide (O 2 2– ) is attributed to both oxygen interstitials and Pr vacancies. The peroxide species limits the oxygen ion migration due to the additional energy required to break its O–O bond, which leads to a decrease in ORR activity. Subsequently, we investigate the diffusion paths of Pr-ions while comparing them with those of other Ln 3+ ions (La, Nd, Pm, Sm, Gd, Tb, Dy, and Ho) in PNO. The formation energies for various Ln 3+ cation occupancies are calculated, as well as segregation energies in CeO 2 (111) surfaces. Lastly, criteria for effective Ln 3+ dopants are developed. La, Nd, and Pm are proposed as potential substituents in PNO to obtain a stable structure.
Ini this work, the phase equilibrium diagram of the CaO-½Ho 2 O 3 -CoO z system was determined at 885 °C in air. This diagram offers compatibility relationships in the ternary oxide system that are essential for processing and for the understanding of properties of several thermoelectric phases in the system. Four three-phase regions and three solid solution tie-line regions were determined in the CaO-½Ho 2 O 3 -CoO z system. In the CaO-Ho 2 O 3 system, while a small solid solution region was identified for (Ho 1-x Ca x )O (3-z)/2 (0 ≤x ≤ 0.14), Ho was not present in the Ca site of CaO. Neither the reported Ho2CoO4 phase in the Ho 2 O-CoO z system nor the Ca-doped (Ho 1+x Ca1-x)CoO 4-z phase was present at 885 °C. No solid solution of the distorted perovskite, (Ho 1-x Cax)CoO 3-z , was established at this temperature. The CaO-CoO z system consists of two calcium cobaltate thermoelectric compounds. The 2D thermoelectric oxide, (Ca 3-x Ho x )Co 4 O 9-z (0 ≤x ≤ 0.5), has a misfit layered structure, and the 1D Ca 3 Co 2 O 6 consists of chains of alternating CoO 6 trigonal prisms and CoO 6 octahedra. Ca 3 Co 2 O 6 was found to be a stoichiometric compound. A comparison of the phase diagrams of the CaO -½ R 2 O 3 -CoO z (R = La, Nd, Eu, and Ho) systems is given.
Lanthanide-doped nanophosphors have emerged as promising optical labels for high-resolution, "multicolor"electron microscopy. Here, we develop a library of 11 unique lanthanide-doped nanophosphors with average edge lengths of 15.2 ± 2.0 nm (N = 4284). These nanophosphors consist of an electron-stable BaYF5 host lattice doped at 25% atomic concentration with the lanthanides Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Tb 3+ , Dy 3+ , Ce 3+ , Ho 3+ , Er 3+ , Tm 3+ , and Yb 3+ . Under ~100 pA/nm 2 beam beam current in a transmission electron microscope, each nanophosphor species exhibits strong cathodoluminescence spectra with sharp characteristic emission lines for each lanthanide. The bright emission and stability of these nanoparticles enable not only ensemble, but also single-particle cathodoluminescence spectroscopy, which we demonstrate with BaYF 5 :Ln 3+ , where Ln 3+ = Tb 3+ , Ho 3+ , Er 3+ , Sm 3+ , Eu 3+ , or Pr 3+ . Single-particle cathodoluminescence corresponds directly with HAADF intensity across nanoparticles, confirming high spatial localization of the measured cathodoluminescence signal of lanthanide-doped nanophosphors. Furthermore, our synthesis and characterization of sub-20 nm, electron-stable nanophosphors provides a robust material platform to achieve single-molecule labeled correlative cathodoluminescence electron microscopy, a critical foundation for high-resolution correlation of single molecules within the context of cellular ultrastructure.
Single crystals of LnFe(SO 4 ) 3 (H 2 O) 2 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm; compounds 1–11) and LnFe(SO 4 ) 3 (H 2 O) (Ln = Tm, Yb, Lu; compounds 12–14) were synthesized under hydrothermal conditions. Single-crystal X-ray diffraction (SCXRD) analysis revealed that the dihydrated compounds (1–11) crystallize in centrosymmetric (CS) structures, with the lanthanide ions adopting eight-coordinate geometries. In contrast, the monohydrated compounds (12–14) exhibit noncentrosymmetric (NCS) structures, where the lanthanide ions are seven-coordinated. Vibrating sample magnetometry (VSM) confirmed that compounds 2, 4, and 7–11 are paramagnetic below 400 K, with compound 8 displaying the highest magnetic susceptibility. Compounds 1, 5, 6, 13, and 14 show a sharp increase in magnetic susceptibility at Néel temperatures ( T N ) of approximately 72, 76, 70, 58, and 56 K, respectively, indicating antiferromagnetic ordering. High-temperature magnetic susceptibility measurements further support the presence of antiferromagnetic transitions in these compounds. Second harmonic generation (SHG) measurements showed that the noncentrosymmetric Yb (compound 13) and Lu (compound 14) compounds exhibit SHG intensities of 0.3× and 1.6× that of potassium dihydrogen phosphate (KDP), respectively.
Recent studies have established Van der Waals (vdW) layered and 2D rare-earth tritellurides (RTe 3 ) as superconductors and near room-temperature charge density wave (CDW) materials. Their environmental stability raises natural concern owing to aging/stability effects observed in other tellurium-based layered crystals. Here, the results establish the stability and environmental aging characteristics of these RTe 3 systems involving a variety of metals such as La, Nd, Sm, Gd, Dy, and Ho. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) results show that all the RTe 3 sheets oxidize to form thin TeO x layers that are primarily confined to the surface, edges, and grain boundaries. Time-resolved in situ Raman spectroscopy measurements are used to understand the kinetics of the oxidization process for different lanthanide metal cations and establish their relative stability/resilience to oxidization. Overall results indicate that the vdW layers show higher air stability as the 4f electron number decreases going from Ho to La, resulting in the most stable LaTe 3 compared to the least stable HoTe 3 . Comprehensive quantum mechanical simulations reveal that environmental degradation originates from a strong oxidizing reaction with O 2 molecules, while humidity (H 2 O) plays a negligible role unless Te vacancies are present. Moreover, the simulations explain the effects of 4f electrons on the work function and Te vacancies formation, which directly impact the aging characteristics of RTe 3 layers. Interestingly, optical and electrical measurements show that the CDW response is still observed in aged RTe 3 layers owing to the presence of underlying pristine/nonoxidized RTe 3 layers, except CDW transition temperatures increase due to the thickness effect. Overall results offer the first in-depth environmental aging studies on these materials, which can be applied to engineer and design their chemical stability, surface properties, and overall CDW characteristics.
A set of mechanically interlocked molecules (MIMs) can be synthesized efficiently using a one-pot procedure by selecting different trivalent lanthanide metal cations (M 3+ , M = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu) and adjusting the proportion of the reaction components. In this system, a flexible tetracationic macrocycle, often referred to as the “Texas-sized molecular box”, interacts with terephthalate dianions and trivalent lanthanide metal cations to form various structures. The transition from metal-organic rotaxane frameworks (MORFs) to metal-containing rotaxane supramolecular organic frameworks (RSOFs) is largely dictated by the lanthanide contraction effect, which leads to a decrease in the coordination number of the lanthanide ions. In addition, the nature of the MIMs within the MORFs can be fine-tuned by varying the ratio of the cation to the other components, allowing for additional control over the interlocked system. Furthermore, these findings demonstrate that the choice of metal cation and adjustments in the building block ratios component represent promising strategies for controlling the structures of MIM-based frameworks.
The rare-earth tritellurides (RTe 3 , where R = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Y) form a charge density wave state consisting of a single unidirectional charge density wave for lighter R, with a second unidirectional charge density wave, perpendicular and in addition to the first, also present at low temperatures for heavier R. In this paper, we present a quantum oscillation study in magnetic fields up to 65T that compares the single charge density wave state with the double charge density wave state both above and below the magnetic breakdown field of the second charge density wave. In the double charge density wave state it is observed that there remain several small, light pockets with the largest occupying around 0.5% of the Brillouin zone. By applying magnetic fields above the independently determined magnetic breakdown field, the quantum oscillation frequencies of the single charge density wave state are recovered, as expected in a magnetic breakdown scenario. Measurements of the electronic effective mass do not show any divergence or significant increase on the pockets of Fermi surface observed here as the putative quantum phase transition between the single and double charge density wave states is approached.