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Article

An Organic–Inorganic Hybrid Semiconducting Quantum Spin Liquid Candidate: (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O]

by
Bin Zhang
1,*,†,
Yan Zhang
2,*,†,
Dongwei Wang
3,
Zheming Wang
4,*,
Guangcai Chang
5,
Zengqiang Gao
5,
Yanjun Guo
3,
Fen Liu
6,
Zhijuan Zhao
6,
Xiaoyu Zhang
6,
Baolong Qu
6,
Peng Xu
3,
Jiaou Wang
5,
Fenliang Dong
3,
Tongling Liang
6,
Yang Sun
6,
Deliang Yang
6,
Qiaolian Li
6,
Xiaofei Luo
6,
Rongjuan Feng
6,
Mei Liu
6 and
Xueying Zhang
6add Show full author list remove Hide full author list
1
Organic Solid Laboratory, BNLMS, CMS & Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
2
Institute of Condensed Matter and Material Physics, School of Physics, Peking University, Beijing 100871, China
3
CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology, Beijing 100190, China
4
State Key Laboratory of Rare Earth Materials Chemistry and Applications, BNLMS, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
5
BSRF, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100047, China
6
Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
*
Authors to whom correspondence should be addressed.
†
These authors contributed equally to this work.
Magnetochemistry 2025, 11(2), 12; https://doi.org/10.3390/magnetochemistry11020012
Submission received: 25 November 2024 / Revised: 21 January 2025 / Accepted: 10 February 2025 / Published: 12 February 2025
(This article belongs to the Special Issue Molecular Magnetism: A Themed Issue in Honor of Professor Dai-Zheng Liao on the Occasion of His 85th Birthday)
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Versions Notes

Abstract

:
The organic–inorganic hybrid (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O] (I) was obtained using the electrocrystallization method. It comprises a θ21-phase organic donor layer and a two-dimensional inorganic antiferromagnetic honeycomb lattice. Cu(II) is octahedrally coordinated by three bisbidenetate oxalates, exhibiting Jahn–Teller distortion. CH3CH2OH and H2O molecules are located within the cavities of the honeycomb lattice. The total formal charge of the three donor molecules was assigned to be +2 based on the bond lengths in the TTF core, which corresponded to the Raman spectra. It is a semiconductor with σrt = 0.04 S/cm and Eα = 40 meV. No long-range ordering was observed above 2 K from zero-field cooling/field cooling magnetization, as confirmed by specific heat measurements. The spin frustration with f > 10 from the antiferromagnetic copper-oxalate-framework was observed. It is a candidate quantum spin liquid.

1. Introduction

In 1973, P. W. Anderson proposed that in a S = 1/2 antiferromagnetic interaction triangular lattice, magnetic ordering or freezing is not observed due to spin frustration, resulting in a quantum spin liquid [1]. In 1987, he suggested that the insulating antiferromagnet La2CuO4 acts as the parent compound of the cuprate superconductor after hole doping [2,3]. Quantum spin liquids with two-dimensional lattices, including triangular lattices, Kagome lattices and honeycomb lattices, have been proposed [4,5]. Quantum spin liquids have emerged as a central focus in condensed matter physics due to their strong connection to magnetism and conductivity. Numerous molecular superconductors have been identified within hybrid organic–inorganic charge–transfer complexes [6]. These complexes also provide strong support for research into quantum spin liquid candidates. The behavior of quantum spin liquids was identified in organic–inorganic hybrid charge–transfer complexes, such as κ-(BEDT-TTF)2[Cu2(CN)3] (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene), κ-(BEDT-TTF)2[Ag2(CN)3], EtMe3Sb[Pd(dmit)2]2 (dmit = 1,3-dithiol-2-thione-4,5-dithiolate) and κ-H3(cat-EDT-TTF)2. κ-(BEDT-TTF)2[Cu2(CN)3] features a triangular lattice, while (EDT-TTF-CONH2)6[Re6Se8(CN)6] exhibits a Kagome lattice [7,8,9,10,11].
Oxalate (C2O42−), one of the most commonly used short connectors, plays a crucial role in molecular superconductors, molecular conductors and molecular magnets. The exchange coupling in oxalate-bridged binuclear Cu(II) has been extensively studied [12]. Long-range ordering has been reported in metal–oxalate frameworks, ranging from one-dimensional chains such as K2[Fe(μ-C2O4)(C2O4)], A[Fe(μ-C2O4)Cl2] (A = alkyl ammonium), K2[Co(μ-C2O4)(C2O4)] and [Co(μ-C2O4)(μ-HOC3H6OH)] to two-dimensional layers like [(C4H9)4N][MCr(μ-C2O4)3] (M = Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+), A[MIIFeIII(μ-C2O4)3] (A = ammonium; M = Mn, Fe), [Fe(μ-C2O4)(μ-CH3OH)] and [Fe2(μ-C2O4)3]·4H2O, and extending to three-dimensional metal–oxalate networks such as, [ZnII(bpy)3][MIICrIII(μ-C2O4)3][ClO4] (Z = Mn, Fe, Co, Ni; M = Mn, Fe, Co, Ni, Cu, Zn), [Co(bpy)3][Co2(μ-C2O4)3]ClO4, [(Me4N)6[Mn3Cr4(μ-C2O4)12]·6H2O and [Mn(μ-C2O4)]·0.25H2O. Additionally, a single-chain magnet, [C12H24O6K]0.5[(C12H24O6)(FC6H4NH3)]0.5[Co(H2O)2Cr(μ-C2O4)2(C2O4)], has been reported [13,14,15,16,17,18,19,20,21,22,23,24,25,26].
The magnetism and conductivity of M(C2O4)22−, characterized by a square anion, have been investigated. A molecular conductor with a room-temperature conductivity of 320 S/cm was observed in Mg0.33[Pt(C2O4)2]·5.3H2O. It exhibits a metal-to-insulator transition alongside a spin–Peierls transition [27,28]. When the metal cation was replaced with an organic donor, the paramagnetic conductors (BEDT-TTF)2[Pt(C2O4)2] and (BEDT-TTF)2[Cu(C2O4)2] were obtained, and a metal–insulator transition took place at 65 K [29,30,31].
The magnetism and conductivity of organic–inorganic hybrid charge–transfer complexes composed of an organic donor and M(C2O4)33−, featuring an octahedral anion, were also examined. The first paramagnetic superconductor containing a paramagnetic metal ion, β″-(BEDT-TTF)3[Fe(C2O4)3(H3O)·C6H5CN], along with the semiconductor paramagnets β″-(BEDT-TTF)3[KFe(C2O4)3·C6H5CN] and β″-(BEDT-TTF)3[(NH4)Fe(C2O4)3·C6H5CN], were synthesized [32,33]. The insulating TTF2[Fe(μ-C2O4)Cl2], (BEDT-TTF)[Fe(C2O4)Cl2]·CH2Cl2, semiconductive [BEDT-TTF]2[Fe(μ-C2O4)Cl2] and metallic β-BETS2[Fe(μ-C2O4)Cl2] (BETS = bis(ethylenedithio)tetraselenafulvalene) antiferromagnet were derived from a one-dimensional [Fe(μ-C2O4)Cl2−]n zigzag chain. A π–d interaction between the donor and the anion was observed [14,34,35,36,37]. The metallic ferromagnets β-(BEDT-TTF)3[CrMn(μ-C2O4)3] and β-BETS3[CrMn(μ-C2O4)3]·CH2Cl2 were derived from an oxalate-bridged two-dimensional [CrMn(μ-C2O4)3] anion, which formed a honeycomb lattice. Their magnetic behavior is identical to that of [(C4H9)4N][CrMn(μ-C2O4)3] [18,38,39,40].
The Jahn–Teller effect on the charge–transfer complexes within copper–oxalate frameworks has previously been studied [41]. The ferromagnetic insulator [(CH3)3NH]2[Cu(μ-C2O4)(C2O4)]·2.5H2O and weak ferromagnetic insulator [(C2H5)3NH]2[Cu(μ-C2O4)(C2O4)]·H2O, derived from the one-dimensional zigzag chain [Cu(μ-C2O4)(C2O4)2−], were obtained and characterized [42]. Spin frustration with [Cu2(μ-C2O4)32−], which has a honeycomb lattice, as the quantum spin liquid candidate was discovered in organic–inorganic hybrid charge–transfer complexes, including the insulator [(C3H7)3NH]2[Cu2(μ-C2O4)3·2.2H2O], the semiconductor θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and the conductor θ21-BETS3[Cu2(μ-C2O4)3·2CH3OH] [43,44,45]. A quantum spin liquid candidate from a three-dimensional copper-oxalate-framework with a hyperhoneycomb lattice was studied [46,47]. Further research on the role of the Jahn–Teller effect in organic–inorganic hybrids containing a copper–oxalate framework will help identify molecular conductors/superconductors and quantum spin liquid candidates. A new hybrid organic–inorganic change–transfer complex, θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·C2H5OH·1.2H2O] (I), was obtained, and related work is presented here.

2. Experiment and Discussion

BEDT-TTF was acquired from the TCI company (Tokyo, Japan). [(C2H5)3NH]2Cu2(μ-C2O4)3 was synthesized from Cu(NO3)2·6H2O, and H2C2O4·2H2O and (C2H5)3N were synthesized from CH3OH, which was confirmed through elemental analysis, IR spectra and powder X-ray diffraction [46]. A total of 5.0 mg of BEDT-TTF and 30.0 mg of [(C2H5)3NH]2Cu2(μ-C2O4)3 were dissolved in a mixture of 25.0 mL of distilled C6H5Cl and 5.0 mL of distilled C2H5OH, and the mixture was then placed in an electrocrystallization cell. The cell was subjected to a constant source of 0.20 mA at room temperature. Shiny black, thin-plate crystals of compound (I) were obtained on the cathode after two weeks. The single crystals, with fresh crystal surface cleavage carried out using scotch tape, were utilized for EDS and XPS experiments [48]. The element analysis carried out using EDS revealed a composition ratio of S:Cu = 12:1, indicating a donor-to-Cu ratio of 3:2. The characteristic photoelectron peaks of Cu2p, S2p, O1S and C1S were detected in the XPS spectra.
A piece of the single crystal was selected for use in single-crystal X-ray diffraction experiments at the Beijing Radiation Synchrony Facility using λ = 0.70 Å at 290 K, a Rigaku SuperNova diffractometer with Mo radiation (λ = 0.71073 Å) at 290 K, 180 K and 120 K and a Rigaku XtalAB synergy R, HyPix diffractometer with Cu (λ = 1.54184 Å) at 100 K. The crystal structure was solved using the direct method and refined with the full-matrix least-square of F2 using the SHELXL program [49]. The non-hydrogen atoms on BEDT-TTF, Cu, oxalate were refined anisotropically. The hydrogen atoms on BEDT-TTF were located through calculation, and refined isotropically. The solvent molecules present in the cavity were defined by the solvent MASK program. The crystals from different cells were subjected to a single-crystal X-ray diffraction experiment. The crystal structure remained the same. The compound remained stable from 290 K to 100 K. The crystallographic data from the experiments carried out at 290 K, 180 K and 120 K are listed in Table S1. The following discussion refers to the data from the experiment carried out at 100 K.
Compound I crystallizes in a triclinic system with the following cell parameters: a = 8.6724(2) Å; b = 16.7949(6) Å; c = 19.5607 Å; α = 74.096(3)°; β = 89.296(2)°; γ = 88.086(2)°; V = 2738.5(1) Å3; and Z = 2, P 1 at 100 K. There are 2 full and 2 half BEDT-TTF molecules, 2 Cu, 3 oxalates, 2 half ethanol molecules, 0.7 H2O and 0.5 H2O in an independent unit (Figure 1). This is different from θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and θ21-(BETS-TTF)3[Cu2(μ-C2O4)3·2CH3OH], which have three donor molecules, two Cu, three oxalates and two methanol molecules which coexist in an independent unit.
The donor molecules are stacked face-to-face along the a axis to create a donor column. Donor columns are arranged side-by-side along the b axis to form a donor layer in the form of a θ21-phase, which is observed in θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and θ21-(BETS-TTF)3[Cu2(μ-C2O4)3·2CH3OH] (Figure 2) [44,45]. One of the ethylene groups on BEDT-TTF is disordered at 290 K and ordered below 180 K. This is similar to [(C2H5)3NH]2[Cu2(μ-C2O4)3], which exhibits a disorder-to-order transition of its ethylene group at 170 K [46]. There are also S···S contacts between donor molecules.
Cu2+ is octahedrally coordinated by six O atoms from three bisbidentate oxalate ligands. The Cu1–O distances are 1.960(4)~2.045(4) Å in the equatorial plane and 2.230(4) Å and 2.362(6) Å from the apex. The Cu2–O distances are 1.969(5)~1.999(5) Å in the equatorial plane and 2.231(4) Å and 2.327(6) Å from the apex. The elongated bonds in the Jahn–Teller distorted octahedron around Cu are highlighted with blue solid lines (Figure 3). Cu1 and Cu2 are adjacent to each other. A honeycomb lattice is formed in the ab plane as observed in [(C3H7)3NH]2[Cu2(μ-C2O4)3·2.2H2O], θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and θ21-(BETS-TTF)3[Cu2(μ-C2O4)3·2CH3OH] (Figure 3) [43,44,45]. Solvent molecules occupy the cavities of the honeycomb lattice. The two donor layers are separated by an anion sheet along the c axis (Figure 4). Hydrogen bonds exist between the donor and anion, as well as between the anion and solvent molecules (Figure 4).
Considering the bond length of a TTF core with a standard deviation of 0.1 of δ, the oxidation state of ET1 is +2/3, while ET2 and ET3 have oxidation states greater than +2/3, and ET4 has an oxidation state less than +1/2. The oxidation states of ET2 and ET3 decreased as the temperature increased. At 290 K, the oxidation states are +0.70 for ET1, +2/3 for ET2, +2/3 for ET3 and +0.43 for ET4. The total oxidation state in an independent unit is +1.98 (Table 1) [50].
The C=C stretching frequency of the charge–transfer complexes of BEDT-TTF serves as a reliable metric for determining the oxidation state of BEDT-TTF [51]. In the Raman spectra (λ = 514.5 nm), a broad band was observed at 1490 cm−1 (Figure 5). This corresponds to charge–transfer complexes with BEDT-TTF+2/3 and is similar to the 1493 cm−1 band observed for θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] [44]. The weak band at 1427 cm−1 is attributed to ET2, corresponding to an oxidation state ranging from +1/4 to +3/4. It aligns with the formal charge assigned based on the bond lengths in the TTF core.
The conductivity measurement was conducted using a four-probe method in a Quantum Design PPMS 9 system. Gold wire was affixed to the best-developed surface of a single crystal with gold paste. The room-temperature conductivity was σrt = 0.02 S/cm. This value is lower than σrt = 4 S/cm for θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH], and significantly lower than σrt = 140 S/cm for θ21-(BETS-TTF)3[Cu2(μ-C2O4)3·2CH3OH] [44,45]. The conductivity decreased as the temperature dropped, with Eα = 40 meV indicating semiconductor behavior (Figure 6).
The unpaired electron of Cu(II) is located in the magnetic orbital dx2−y2 within the equatorial plane. The orbital corresponding to the elongated octahedral Cu(II) is the dz2 orbital, as indicated by the blue solid line highlighted in Figure 3. The magnetic configuration is a stripy antiferromagnetic state [52]. Since the antiferromagnetic interaction is stronger than the ferromagnetic interaction between oxalate-bridged Cu(II) atoms, an antiferromagnetic behavior is expected [12].
The magnetic susceptibility measurement was carried out on Quantum Design MPMS 7XL system. The susceptibility data were corrected by the Pascal constant of the sample and the sample holder [53].
At 300 K, the χT value was 0.389 cm3 K mol−1 and g was 2.04. This is consistent with an isolated, spin only Cu(II) ion with S = 1/2 and g = 2.00 [54]. As the temperature decreased, the χ increased smoothly, exhibiting a bend around 230 K, followed by an upturn at 22 K. The data fitted to the Curie–Weiss law yielded C = 0.503(2) cm3 mol−1, θ = −87(2) K and R = 9.6 × 10−7 above 230 K, while C = 0.405(1) cm3 mol−1, θ = −25.2(7) K and R = 1.3 × 10−5 from 100 K to 230 K (Figure 7). No bifurcation is observed from zero-field-cooling magnetization and field-cooling magnetization (ZFCM/FCM) above 2 K under 100 G (Figure 8). No long-range ordering was detected above 2 K. As such, it is a spin-frustrated complex with f > 12 [54].
Specific heat measurements were performed from 2 to 120 K under 0 T and 8 T, utilizing a Quantum Design PPMS9 system (Figure 9). No λ-peak was detected in the range of 2 to 120 K. When combined with the X-ray diffraction experiment from 280 K to 120 K, there was no long-range order observed above 2 K.
Isothermal magnetization at 2 K increased with the magnetic field, reaching 0.162 Nβ at 65 kG (Figure 10). This value surpasses the 0.077 Nβ for θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH], 0.076 Nβ of θ21-(BETS-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and 0.040 Nβ for [(C3H7)3NH]2[Cu2(μ-C2O4)3·2.2H2O] at 2 K and 65 kG [42,43,44].
Compared with θ21-(BEDT-TTF)3[Cu2(μ-C2O4)3·2CH3OH] and θ21-(BETS-TTF)3 [Cu2(μ-C2O4)3·2CH3OH], the conductivity is contributed by the organic donor. The solvent molecule influences the magnetic properties of compounds.

3. Conclusions

In this study, we show an organic–inorganic hybrid charge–transfer complex composed of a θ21-phase organic donor layer and an inorganic sheet featuring a honeycomb lattice. The Jahn–Teller effect on the transport and magnetism of organic-inorganic hybrid charge–transfer complexes, influenced by solvent molecules hosted in the honeycomb Cu-oxalate-framework, was studied. It exhibits a semiconducting behavior with Eα = 40 meV. An antiferromagnetic interaction with the spin frustration f > 10 occurs, with no long-range order observed above 2 K. Thus, it is a candidate semiconducting quantum spin liquid.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/magnetochemistry11020012/s1, Table S1. The crystallographic data of I at 290 K, 180 K, 120 K. Table S2. Bond lengths of Cu–O in I at 290 K, 180 K and 120 K. Table S3. Bond lengths of the TTF core in BEDT-TTF of I at 290 K, 180 K and 120 K. X-ray crystallographic data supplied by CCDC 2417702/2412001/2417459/2417460.

Author Contributions

The manuscript was written with the contributions of all authors. Funding acquisition B.Z.; B.Z. and Y.Z. synthesized the sample.; Y.Z. Performed the transport and magnetic measurements; G.C., Z.G., Z.W., T.L. and Y.S. performed the X-ray experiments and data analysis: D.W. performed specific heat experiment and data analysis; Y.G. performed Raman experiment and data validation; F.L., Z.Z., X.Z. (Xiaoyu Zhang), B.Q., P.X. and J.W. performed the XPS experiments and data validation, F.D. performed thin film of crystal, D.Y. performed the EDS experiment, Q.L. and X.L., performed element anlysis and R.F. performed IR spectra measuremetn. M.L. and X.Z. (Xueying Zhang) performed data valiation, B.Z., Y.Z. and Z.W. analyzed all of the data. B.Z., Y.Z. and Z.W. wrote the main manuscript text. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Natural Science Foundation of China: 22273109, 22073106, 21573242 and 21173230.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

CCDC 2417702/2412001/2417459/2417460 contain the supplementary crystallographic data for compounds I at 100 K, 120 K, 180 K and 290 K, respectively. These data can be obtained free of charge via https://www.ccdc.cam.ac.uk/structures/ (accessed on 21 January 2025) or from Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033; or e-mail: deposit@ccdc.cam.ac.uk. The original contributions presented in this study are included in the article/Supplementary Material. Further inquiries can be directed to the corresponding authors.

Conflicts of Interest

The authors declare no conflicts of interest.

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Magnetochemistry 11 00012 g001
Figure 1. Atoms in an independent unit of I.
Figure 1. Atoms in an independent unit of I.
Magnetochemistry 11 00012 g001
Magnetochemistry 11 00012 g002
Figure 2. Donor arrangement of I on the ab plane. Dashed yellow lines are S···S contacts. ET is an abbreviation for BEDT-TTF.
Figure 2. Donor arrangement of I on the ab plane. Dashed yellow lines are S···S contacts. ET is an abbreviation for BEDT-TTF.
Magnetochemistry 11 00012 g002
Magnetochemistry 11 00012 g003
Figure 3. Anion layer of I viewed along the c axis.
Figure 3. Anion layer of I viewed along the c axis.
Magnetochemistry 11 00012 g003
Magnetochemistry 11 00012 g004
Figure 4. Packing diagram of I viewed along the a axis. Color code: Cu, blue; O red: S, yellow; C gray. Hydrogen bond, dashed blue line.
Figure 4. Packing diagram of I viewed along the a axis. Color code: Cu, blue; O red: S, yellow; C gray. Hydrogen bond, dashed blue line.
Magnetochemistry 11 00012 g004
Magnetochemistry 11 00012 g005
Figure 5. Raman spectrum of I with λ = 514.5 nm.
Figure 5. Raman spectrum of I with λ = 514.5 nm.
Magnetochemistry 11 00012 g005
Magnetochemistry 11 00012 g006
Figure 6. Temperature-dependent conductivity of I.
Figure 6. Temperature-dependent conductivity of I.
Magnetochemistry 11 00012 g006
Magnetochemistry 11 00012 g007
Figure 7. 1/χ vs. T (empty black triangle) of I. The red and solid lines are fit to the Curie–Weiss law.
Figure 7. 1/χ vs. T (empty black triangle) of I. The red and solid lines are fit to the Curie–Weiss law.
Magnetochemistry 11 00012 g007
Magnetochemistry 11 00012 g008
Figure 8. ZFCM/FCM of polycrystal under 100G.
Figure 8. ZFCM/FCM of polycrystal under 100G.
Magnetochemistry 11 00012 g008
Magnetochemistry 11 00012 g009
Figure 9. Specific heat of I from 2 K to 120 K.
Figure 9. Specific heat of I from 2 K to 120 K.
Magnetochemistry 11 00012 g009
Magnetochemistry 11 00012 g010
Figure 10. Isothermal magnetization of I at 2 K.
Figure 10. Isothermal magnetization of I at 2 K.
Magnetochemistry 11 00012 g010
Table 1. Bond lengths of the TTF core in BEDT-TTF of I at 100 K.
Table 1. Bond lengths of the TTF core in BEDT-TTF of I at 100 K.
Magnetochemistry 11 00012 i001
δ = (b + c) − (a + d)
Q = 6.347 − 7.463δ
abcdδQ
ET11.370



~1.370 *		1.741
1.740
1.735
1.746
~1.741		1.748
1.756
1.750
1.758
~1.753		1.363
1.359


~1.361		0.7630.65
ET21.379



~1.370		1.737
1.734
1.733
1.734
~1.735		1.748
1.746
1.752
1.741
~1.747		1.362
1.355


~1.359		0.7440.80
ET31.382

~1.382		1.722
1.728
~1.725		1.744
1.746
~1.745		1.352

~1.352		0.7360.85
ET41.354

~1.354		1.753
1.756
~1.755		1.756
1.765
~1.761		1.337

~1.337		0.8240.20
Total 1.975 **
* The average value of bond lengths. ** Total charge of two and two half donors in an independent unit: ΣQ = QET1 + QET2 + 1/2QET3 + 1/2ET4.
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Zhang, B.; Zhang, Y.; Wang, D.; Wang, Z.; Chang, G.; Gao, Z.; Guo, Y.; Liu, F.; Zhao, Z.; Zhang, X.; et al. An Organic–Inorganic Hybrid Semiconducting Quantum Spin Liquid Candidate: (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O]. Magnetochemistry 2025, 11, 12. https://doi.org/10.3390/magnetochemistry11020012

AMA Style

Zhang B, Zhang Y, Wang D, Wang Z, Chang G, Gao Z, Guo Y, Liu F, Zhao Z, Zhang X, et al. An Organic–Inorganic Hybrid Semiconducting Quantum Spin Liquid Candidate: (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O]. Magnetochemistry. 2025; 11(2):12. https://doi.org/10.3390/magnetochemistry11020012

Chicago/Turabian Style

Zhang, Bin, Yan Zhang, Dongwei Wang, Zheming Wang, Guangcai Chang, Zengqiang Gao, Yanjun Guo, Fen Liu, Zhijuan Zhao, Xiaoyu Zhang, and et al. 2025. "An Organic–Inorganic Hybrid Semiconducting Quantum Spin Liquid Candidate: (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O]" Magnetochemistry 11, no. 2: 12. https://doi.org/10.3390/magnetochemistry11020012

APA Style

Zhang, B., Zhang, Y., Wang, D., Wang, Z., Chang, G., Gao, Z., Guo, Y., Liu, F., Zhao, Z., Zhang, X., Qu, B., Xu, P., Wang, J., Dong, F., Liang, T., Sun, Y., Yang, D., Li, Q., Luo, X., ... Zhang, X. (2025). An Organic–Inorganic Hybrid Semiconducting Quantum Spin Liquid Candidate: (BEDT-TTF)3[Cu2(μ-C2O4)3·CH3CH2OH·1.2H2O]. Magnetochemistry, 11(2), 12. https://doi.org/10.3390/magnetochemistry11020012

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