Darago L.E., Aubrey M.L., Yu C.J. et al. · Journal of the American Chemical Society · 2015 · 15703-15711
Open a family to keep every result attached to its sample, method and conditions.
Paraphrased for this database from the authors’ stated interpretations — never quoted verbatim — and kept separate from reported measurements.
Chemical reduction to 2 and to Na3.2(NBu4)1.8Fe2(dhbq)3 largely retains the crystallographic framework of 1.
Caveat: Na3.2 derivative formula is putative because C/H/N elemental analysis was unsuccessful.
4 · Chemical Reduction of 1 · Figures S3-S4 · Linked to 2 structured results
UV-vis-NIR diffuse reflectance reveals Robin-Day Class II/III mixed valency in a MOF, evidenced by broad low-energy IVCT bands and a sharp absorption edge.
Caveat: High-energy feature at 21500 cm^-1 is only tentatively assigned and may include ligand-to-metal charge transfer.
5 · UV-Vis-NIR Diffuse Reflectance Spectroscopy · Figure 6 · Linked to 4 structured results
The ferric semiquinoid lattice gives both electronic transport and ferrimagnetic ordering; increasing dhbq3- density in 2 raises ordering temperature from 8 K to 12 K.
Caveat: Low ordering temperatures are attributed to competing ferro- and antiferromagnetic interactions.
7 · Conclusions and Outlook · Figure 8 · Linked to 4 structured results
Although the interpenetrated framework is structurally porous, NBu4+ countercations fill the pores nearly completely and activated 1 lacks microporosity.
Caveat: Only uptake isotherms for 1 are shown; no BET area is reported.
3 · Results and Discussion · Figure S1 · Linked to 3 structured results
Post-synthetic reduction from 1 to 2 decreases conductivity despite increasing radical density, implying charge-carrier mobility dominates over carrier density in these materials.
Caveat: Conductivity was measured on pressed pellets with possible contact and grain-boundary limitations.
6 · Electronic Conductivity · Figure 7 · Linked to 5 structured results
The electronic conductivity in 1 and 2 originates from ligand mixed-valency and electron hopping within the dhbq2-/3- redox manifold rather than iron-centred reduction.
Caveat: Two-point pellet conductivity can be affected by crystallite boundaries and electrode contacts.
5 · Electronic Conductivity · Figures 6-7 · Linked to 5 structured results
Names and aliases are kept exactly within the paper’s own identity model.
| Material | Composition | Structure context | Source |
|---|---|---|---|
| (NBu4)2FeIII2(dhbq)3 (1) | (NBu4)2FeIII2(dhbq)3; empirical formula C50H78Fe2N2O12High-spin FeIII centres. · Mixed-valent dhbq2-/dhbq3- linkers derived from 2,5-dihydroxybenzoquinone; charge balance implies 2:1 dhbq3-:dhbq2- ratio. | 3D · PristineCubic I-43d framework of two interpenetrated (10,3)-a nets of opposing chirality; tetrabutylammonium countercations fill pores. | 3 · Results and Discussion · Figure 2 |
| Na0.9(NBu4)1.8FeIII2(dhbq)3 (2) | Na0.9(NBu4)1.8FeIII2(dhbq)3; calculated C46.8H70.8Fe2N1.8Na0.9O12High-spin FeIII centres retained after reduction. · Reduced mixed-valent dhbq linkers; charge balance gives about 2.7:0.3 dhbq3-:dhbq2- ratio. | 3D · PristinePost-synthetically reduced derivative of 1; PXRD almost overlays with simulated 1, indicating little unit-cell change. | 4 · Chemical Reduction of 1 · Figure S3 |
| Na3.2(NBu4)1.8Fe2(dhbq)3 | Na3.2(NBu4)1.8Fe2(dhbq)3Fe sites assigned preferentially as high-spin FeIII, although one site could possibly be low-spin FeII. · More strongly reduced dhbq framework, interpreted as ligand-based reduction generating dhbq3- and then thb4- ligands. | 3D · PristineStrongly reduced derivative with PXRD almost overlaying 1; formula is putative due to unsuccessful C/H/N analysis. | S-3 · Experimental Details · Figure S4 |
Sample form, processing state and composition status define the context for measurements.
| Sample | Form and role | Processing and geometry | Source |
|---|---|---|---|
| Black cubic crystals of 1research_0186__mat__mat_1_nbu4_fe_dhbq | Single Crystal · Target Sample · Pristine Framework | Recovered by vacuum filtration inside a N2 glovebag and dried at 150 C under reduced pressure for 1 h. | 2 · Experimental Section |
| Composite electrochemical electrode containing 1research_0186__mat__mat_1_nbu4_fe_dhbq | Electrode · Composite Sample · Composite | Drop-cast slurry electrode prepared in Ar glovebox.carbon cloth | S-5 · Electrochemical Methods |
| Pressed pellet of 1research_0186__mat__mat_1_nbu4_fe_dhbq | Pellet · Target Sample · Pristine Framework | Pellet pressed between polished copper rods in an argon glovebox for sealed two-point conductivity cell.300 to 700 um typical; thicker pellets used for 1 | S-5 · Variable Temperature Two-Point Electronic Conductivity · Scheme S1 |
| Microcrystalline/crystalline powder of 1research_0186__mat__mat_1_nbu4_fe_dhbq | Powder · Target Sample · Pristine Framework | Crystalline solid of 1 handled under inert atmosphere; heated at 150 C under vacuum for porosity measurements. | S-8 · Figure S1 caption · Figure S1 |
| Pressed pellet of 2research_0186__mat__mat_2_na09_nbu4_fe_dhbq | Pellet · Target Sample · Doped | Pellet pressed between polished copper rods in an argon glovebox for sealed two-point conductivity cell.300 to 700 um typical | S-5 · Variable Temperature Two-Point Electronic Conductivity · Scheme S1 |
| Brown microcrystalline powder of 2research_0186__mat__mat_2_na09_nbu4_fe_dhbq | Powder · Target Sample · Doped | Post-synthetically reduced from 1 with sodium naphthalenide in THF; washed with THF and dried under reduced pressure. | 2 · Experimental Section |
| Dark brown microcrystalline powder of Na3.2(NBu4)1.8Fe2(dhbq)3research_0186__mat__mat_3_na32_nbu4_fe_dhbq | Powder · Target Sample · Doped | Post-synthetically reduced from 1 with 4 equiv sodium naphthalenide per mole of 1. | S-3 · Experimental Details |