Sippel P., Denysenko D., Loidl A. et al. · Advanced Functional Materials · 2014 · 3885-3896
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.
Replacing Zn(II) by high-spin Co(II) narrows the intrinsic band gap of Co-MFU-4 through an empty Co-derived band below the MFU-4 conduction-band energy.
Caveat: The authors cannot unambiguously choose whether the low- or high-energy optical feature should be compared to the periodic calculated Co-MFU-4 gap.
p010 · Conclusion · Fig. 14 · Linked to 4 structured results
MFU-4-type semiconducting MOFs can be band-gap engineered by increasing ligand conjugation or by choosing metals with suitable d-orbital energies, especially octahedral metals with unoccupied d orbitals below the ligand LUMO.
Caveat: The 4d/5d transition-metal extension is predicted as a design strategy and not demonstrated experimentally in this paper.
p010 · Conclusion · Fig. 14 · Linked to 3 structured results
Band conduction is the dominant charge-transport mechanism in MFU-4, similar to conventional semiconductors.
Caveat: Conductivity values are very low and inferred from dielectric spectroscopy rather than conventional dc transport.
p010 · Conclusion · Fig. 8 / Fig. 10 / Table 1 · Linked to 3 structured results
In Co-MFU-4, hopping conductivity of localized electrons may play an important role, unlike the clearer band-conduction behaviour of MFU-4.
Caveat: A variable-range hopping plot did not linearise the full sigma_dc(T) data; the paper frames hopping as likely/important rather than fully resolved.
p002 · Introduction · text · Linked to 2 structured results
The main low-temperature relaxation process in MFU-4 arises from reorientation of residual/occluded DMF molecules in framework pores.
Caveat: The microscopic origin of additional processes II and III remains speculative; residual water or intramolecular modes cannot be excluded.
p010 · Conclusion · Fig. 5-Fig. 7 · Linked to 3 structured results
Names and aliases are kept exactly within the paper’s own identity model.
| Material | Composition | Structure context | Source |
|---|---|---|---|
| Co-MFU-4 | Co5Cl4(BBTA)3 framework repeat unit; periodic unit cell described as 4[Co5Cl4(BBTA)3]Co(II) ions substituting Zn(II) sites in Kuratowski-type [Co5Cl4] secondary building units; high-spin Co(II) considered in calculations · benzo[1,2-d:4,5-d']bis([1,2,3]triazolate) (BBTA2-) | 3D · PristineIsostructural with MFU-4 based on atom positions and crystallographic symmetry after substituting all Zn2+ by Co2+. | p002 · Introduction · text |
| N,N-dimethylformamide | C3H7NO | 0D · Model SystemSolvent/guest molecule occluded in MFU-4 pores and separately modelled as a pure liquid molecular ensemble. | p005 · Relaxation Dynamics · Fig. 6 / Fig. 7 |
| MFU-4 | Zn5Cl4(BBTA)3 framework repeat unit; periodic unit cell described as 4[Zn5Cl4(BBTA)3]Zn(II) ions in Kuratowski-type [Zn5Cl4] secondary building units with octahedral and tetrahedral Zn sites · benzo[1,2-d:4,5-d']bis([1,2,3]triazolate) (BBTA2-) | 3D · PristineCubic MFU-4 framework, space group Fm-3m (reported as Fm(1)m), no. 225, a = 21.697(3) A; cubic face-centred unit cell has four near-spherical cavities. | p002 · Introduction · Fig. 1 / text |
Sample form, processing state and composition status define the context for measurements.
| Sample | Form and role | Processing and geometry | Source |
|---|---|---|---|
| Co-MFU-4 powder heated at 280 C under vacuumresearch_0755__mat__mat_comfu4 | Powder · Target Sample · Pristine Framework | DMF removed by heating 16 h at 280 C under vacuum; dielectric samples also evacuated before measurement | p010 · Experimental Section · text |
| Co5Cl4(HBBTA)6 Co-MFU-4 cluster modelresearch_0755__mat__mat_comfu4 | Model · Model System · Model | Gaussian09 HSE/Def2-TZVP cluster model M5Cl4(HBBTA)6 with M = Co(II); highest-spin S = 7.5 lowest in energy | p008 · Cluster Calculations · text |
| Periodic Co-MFU-4 unit-cell modelresearch_0755__mat__mat_comfu4 | Model · Model System · Model | Periodic DFT model containing 204 atoms with composition 4[Co5Cl4(BBTA)3] | p008 · Quantum Mechanical Calculations · text |
| DMF@MFU-4 MD modelresearch_0755__mat__mat_mfu4 | Model · Model System · Model | 2x2x2 MFU-4 supercell with 192 DMF molecules, six DMF per void cavity, force-field MD at 298 K | p016 · Electrical Poling Behaviour of DMF@MFU-4 · text / Fig. S17 |
| Pure DMF MD/liquid referenceresearch_0755__mat__mat_dmf | Model · Model System · Model | Cubic box containing 192 DMF molecules for MD; bulk/supercooled DMF also measured for relaxation comparison | p015 · Electrical Poling Behaviour of DMF@MFU-4 · text / Fig. S16 |
| MFU-4 powder heated at 280 C under vacuumresearch_0755__mat__mat_mfu4 | Powder · Target Sample · Pristine Framework | DMF removed by heating 16 h at 280 C under vacuum; subjected to vacuum for 48 h before dielectric runs | p010 · Experimental Section · text |
| MFU-4 powder heated at 320 C under high vacuumresearch_0755__mat__mat_mfu4 | Powder · Target Sample · Pristine Framework | Heated to 320 C under vacuum/high vacuum to remove occluded DMF | p002 · Introduction · text |
| As-prepared DMF-loaded MFU-4 powderresearch_0755__mat__mat_mfu4 | Powder · Target Sample · Guest Loaded | Measured as prepared without removing DMF | p010 · Experimental Section · text |
| Zn5Cl4(HBBTA)6 MFU-4 cluster modelresearch_0755__mat__mat_mfu4 | Model · Model System · Model | Gaussian09 HSE/Def2-TZVP cluster model M5Cl4(HBBTA)6 with M = Zn(II) | p008 · Cluster Calculations · Fig. S11 / text |
| Periodic MFU-4 unit-cell modelresearch_0755__mat__mat_mfu4 | Model · Model System · Model | Periodic DFT model containing 204 atoms with composition 4[Zn5Cl4(BBTA)3] | p011 · Experimental Section, Quantum Mechanical Investigations · text |