Christopher H. Hendon, Davide Tiana and Aron Walsh · Physical Chemistry Chemical Physics · 2012
Review whether hybrid organic-inorganic frameworks and networks can be designed as electrically conductive or semiconducting materials, with emphasis on transport physics, metal/ligand selection, modelling and unresolved design principles.
The review’s argument is preserved as a navigable set of section summaries.
Discusses porous 3D frameworks, especially MOF-5, low-conductivity Cu/Ag examples, redox-electrolyte use in pores and photochromic TiO2-based frameworks.
Relevance: Core · 13128 · 3D Porous metal organic frameworks
Moves to 2D and higher-dimensional hybrids, focusing on structural motifs, metal selection, ligand selection and how local structure complicates electronic design rules.
Relevance: Core · 13125 · Beyond 1D
States that conductive/light-absorbing hybrid systems have progressed, but high-efficiency device applications and transparent design rules remain absent; proposes modelling, thin films, devices and manufacturing as the path forward.
Relevance: Core · 13129 · Conclusions and challenges
Introduces hybrid semiconductors as a new paradigm formed from organic and inorganic building blocks, but still poorly understood and difficult to control.
Relevance: Core · 13122 · Hybrid frameworks
Summarises band-gap excitation, carrier mobility/lifetime requirements, intrinsic versus doped wide-gap behaviour, polaron localisation and the Mott criterion.
Relevance: Core · 13122 · Inorganic semiconductors
Frames conductive hybrid frameworks as a developing field seeking to combine inorganic semiconductor performance with organic/coordination-chemistry flexibility; introduces the risk of over-calling semiconducting behaviour from optical gaps alone.
Relevance: Core · 13121 · Introduction
Reviews 1D coordination polymers, charge-transfer systems, phthalocyanine motifs, metal-metal contacts and ligand-centred donor/acceptor design as benchmark routes to electrical activity.
Relevance: Core · 13123 · Metal-organic polymers
Contrasts organic materials with inorganic semiconductors, emphasising conjugated pi systems, p-type dominance, disorder-driven localisation, hopping/tunnelling, anisotropy and defect-derived carriers.
Relevance: Core · 13122 · Organic semiconductors
Classification systems are attributed to this review and are not treated as a global material registry.
Figure 2 classifies basic 1D coordination-polymer motifs used as simple benchmark systems for hybrid conduction.
Categories: linear · ribbon · ladder · metal cluster · zigzag
13123 · Metal-organic polymers · Fig. 2
The review organises 1D CP conduction by the electronic interaction that links carriers through or between components.
Categories: ligand pi* to metal d-pi overlap · metal-metal contact · interlayer pi-pi overlap · donor-acceptor charge transfer · peripheral S-S inter-stack contact
13123 · Metal-organic polymers
The review adopts a dimensionality notation for classifying hybrid frameworks according to the connectedness of inorganic and organic components.
Categories: 1D CPs · 2D metal-organic networks · 3D MOFs · I0O1 · I0O2 · I1On · I2On
13121 · Introduction
Provides baseline semiconductor families for comparing hybrid frameworks against established inorganic materials.
Categories: group 14 elemental semiconductors · II-VI semiconductors · III-V semiconductors · multi-component alloys
13121 · Inorganic semiconductors
Separates semiconductors whose thermal carriers are sufficient from materials whose conductivity depends on defect, dopant, thermal or photo-excited carriers.
Categories: intrinsic small-band-gap · wide-band-gap requiring defects or doping
13122 · Inorganic semiconductors
Classifies ligands by whether they mainly tune electronic states, terminate/space layers, create dimensionality or provide pi-electron transport channels.
Categories: halides · chalcogenides · pnictogens · aliphatic amines/diamines · conjugated and aromatic systems
13127 · Ligand selection
The review identifies common metal coordination motifs but cautions that geometry alone does not determine electronic trends.
Categories: cubic · octahedral · tetrahedral · cubane-like dimetallic clusters
13126 · Structural motifs
Uses inorganic and organic semiconductor physics to distinguish band-like carrier motion from localised carrier transport.
Categories: delocalised band transport · localised polaronic states · Anderson localisation · hopping or tunnelling
13122 · Organic semiconductors
Review-defined families retain their representative materials and conduction descriptions.
One-dimensional metal-organic polymers treated as the simplest hybrid frameworks for studying non-covalent interactions and electrical activity.
Conduction: Electrical activity can arise from ligand-metal orbital overlap, charge transfer, pi-pi stacking or metal-metal contacts.
Representative materials: linear CPs · ribbon CPs · ladder CPs · zigzag CPs
Nodes / linkers: varied transition metals · metal clusters · bridging ligands · donor-acceptor ligands · phthalocyanines
13123 · Metal-organic polymers
Two-dimensional hybrid systems using lead/tin/bismuth/copper/zinc and halide, chalcogenide or aromatic ligands to tune optoelectronic properties.
Conduction: Band gaps and dimensionality are strongly ligand- and metal-dependent; local structure can override simple orbital trends.
Representative materials: iodoplumbates · Pb(C6S6) · tin iodide perovskites · copper cubane clusters · ZnSe/SnSe hybrids
Nodes / linkers: Pb · Sn · Bi · Cu · Zn · Y · halides · chalcogenides · benzene hexathiolate · amines · pnictogens
13126 · Beyond 1D
Ag(I)-containing coordination polymers where argentophilic metal-metal contacts and pi-pi interactions may support conductive network formation.
Conduction: Short Ag-Ag distances and combined metal-metal/pi-pi interactions are linked to semiconducting properties and possible 2D network formation.
Representative materials: Ag-cyanopyridine polymers · silver acetate
Nodes / linkers: Ag · cyanopyridine · acetate · pi-stacking organic ligands
13124 · Metal-organic polymers
Copper coordination compounds using TCNQ, DCNQI or TCNE acceptor ligands.
Conduction: Conductivity spans semiconducting Cu-TCNQ values to molecular-metal behaviour in DCNQI-Cu via additional isotropic 3D pathways.
Representative materials: Cu(TCNQ) · Cu(TCNQ)2 · (DCNQI)2Cu · TCNE reductive-coupling products
Nodes / linkers: Cu · TCNQ · DCNQI · TCNE
13124 · Metal-organic polymers
Elemental, binary and multicomponent inorganic materials with band gaps and mobile carriers suitable for electronics or solar-energy conversion.
Conduction: Mostly described by delocalised band transport, with wide-gap materials requiring defect/dopant/thermal/photo carrier generation and possible polaron formation.
Representative materials: Si · Ge · ZnO · CdS · AlN · GaP · InSb
Nodes / linkers: Zn · Cd · Al · Ga · In · not applicable
13121 · Inorganic semiconductors
Porous Zn4O dicarboxylate frameworks often discussed as semiconducting because of optical/photoelectrochemical responses.
Conduction: Reported band gaps around 3.4-3.5 eV, but no solid-state conductivity measurement was known to the review; calculated bands are flat and consistent with localised carriers.
Representative materials: MOF-5 · Zn4O(1,4-dicarboxylate)3
Nodes / linkers: Zn4O clusters · dicarboxylates · 1,4-dicarboxylate
13128 · 3D Porous metal organic frameworks
Molecular conductors, charge-transfer salts and polymeric materials in which conjugated pi systems support charge transport.
Conduction: Often p-type; structural disorder and low dielectric screening favour localisation and thermally activated hopping/tunnelling, though heavy doping can produce metallicity.
Representative materials: pentacene · TTF-TCNQ · naphthalene diimide · Li-doped picene · pi-conjugated polymers
Nodes / linkers: not applicable · conjugated aromatics · donor-acceptor molecules · perylene derivatives
13122 · Organic semiconductors
High electron-affinity organic molecules proposed as promising n-type components for future hybrid metal-organic compounds.
Conduction: Promising n-type mobility and air stability, but oxygen/moisture stability and incorporation into hybrid frameworks remain challenging.
Representative materials: PTCDI-TFB · difluorodioxocyclopentene-annelated terthiophene · BC4B · BC6B
Nodes / linkers: not yet adapted into hybrid compounds · perylenediimides · dicyanomethylene quinoids · annelated terthiophenes
13125 · Metal-organic polymers
Coordination polymers or stacked complexes where phthalocyanine-like ligands and transition metals provide pi-stacked or metal-ligand coupled transport.
Conduction: Better pi-bonding metals and stronger pi-acid ligands improve conductivity; in group 10 stacks, pi-pi overlap rather than direct metal contact is emphasised.
Representative materials: Fe/Ru/Os phthalocyanine bridged CPs · Ni(Pc)(I3)0.33 · group 10 metal phthalocyanines
Nodes / linkers: Fe · Ru · Os · Ni · Pd · Pt · phthalocyanine · pyridine · bipyridine · dabco
13124 · Metal-organic polymers
3D conductive frameworks containing pyrazine-2,3-dithiolate-type thiophene/dithiolene linkers.
Conduction: Room-temperature conductivity approaches 10^-3 S cm-1, among the low but measurable 3D framework conductivities highlighted by the review.
Representative materials: Cu[Cu(pdt)2] · mixed metal Cu-Ni thiophene framework
Nodes / linkers: Cu · Ni · pyrazine-2,3-dithiolate · thiophene/dithiolene ligands
13129 · 3D Porous metal organic frameworks
A dicarboxylate framework built from octameric TiO2 centres that undergoes UV-driven white-to-black photochromism.
Conduction: Band-gap excitation can remove oxygen, creating Ti(III) centres; porosity is interpreted as enabling rapid ion and electron transport.
Representative materials: TiO2 based dicarboxylate framework
Nodes / linkers: TiO2 octamers · Ti(IV)/Ti(III) centres · dicarboxylates
13129 · 3D Porous metal organic frameworks
Hybrid charge-transfer coordination polymers combining TTF with metal dmit complexes.
Conduction: Ni and Pd members are metallic at room temperature; peripheral S-S contacts create 2D networks that avoid simple 1D Peierls instability.
Representative materials: TTF-[Ni(dmit)2] · TTF-[Pd(dmit)2] · TTF-[Pt(dmit)2]
Nodes / linkers: Ni · Pd · Pt · TTF · dmit sulfur-rich ligands
13123 · Metal-organic polymers
Organic donor-acceptor stacks based on tetrathiafulvalene and tetracyanoquinodimethane.
Conduction: Metallic above 60 K with Peierls-driven transition to semiconducting behaviour below that temperature.
Representative materials: TTF-TCNQ
Nodes / linkers: not applicable · TTF donor · TCNQ acceptor
13123 · Metal-organic polymers
Review-level synthesis principles remain separate from primary-study recipes.
Select rigid conjugated ligands to supply pi electrons, promote self-assembly and potentially contribute directly to semiconducting behaviour.
Claimed effects: May produce ordered, self-assembled and electronically active hybrid semiconductors.
Controlling variables: conjugation length · substitution pattern · hydrophobic regions · backbone twist · counter-ion design
Representative materials: benzene hexathiolate hybrids · H2hippb indium framework · tetrazol benzoic acid zinc systems · pyridinium extensions
Caveat: So many variables exist that effects remain difficult to identify methodically.
13128 · Ligand selection
Terminate organic ligands with chalcogen donor atoms to build electronically active hybrid networks and tune band gaps through chalcogen size.
Claimed effects: Increasing chalcogen size is interpreted to decrease band gap and create highly overlapped self-assembled structures.
Controlling variables: S/Se/Te substitution · aromatic core · synthetic viability · metal-chalcogen bonding
Representative materials: Pb(C6S6) · hypothetical Hg(C6Te6)
Caveat: Tellurium analogues may be computationally stable but synthetically implausible; sulphur and oxygen dominate ligand development.
13127 · Ligand selection
Use electronic-structure and atomistic modelling to connect building-block selection, band structure, carrier localisation and feasible design rules.
Claimed effects: Can help elucidate electronic communication, metal/ligand guidelines and doping strategies for complex hybrid frameworks.
Controlling variables: crystal structure · band dispersion · metal/ligand composition · localisation · doping strategies
Representative materials: MOF-5 · iodoplumbates · chalcogenide hybrids
Caveat: The review stresses that modelling is difficult because hybrid framework crystal structures are large and complex.
13129 · Conclusions and challenges
Move from 1D CPs to 2D networks and 3D frameworks to add conduction pathways, avoid one-dimensional instabilities and support devices.
Claimed effects: Can create additional pathways, such as S-S inter-stack or 3D radical pathways, and produce light-harvesting or photovoltaic-relevant networks.
Controlling variables: framework dimensionality · inter-stack contacts · metal-ligand connectivity · network topology
Representative materials: TTF-[Ni(dmit)2] · (DCNQI)2Cu · 2D iodoplumbates
Caveat: Higher dimensionality alone is not sufficient; cubane-like motifs may remain closed or 0D.
13125 · Beyond 1D
Use halide identity to tune valence-state energy, spin-orbit effects and band gaps in hybrid frameworks.
Claimed effects: Larger halides are expected to reduce band gaps, but counterexamples show local structure can reverse trends.
Controlling variables: halide size · iodide versus bromide/chloride · local bonding geometry
Representative materials: iodoplumbates · hybrid perovskite-like halides
Caveat: Pure electronic or molecular-orbital arguments fail quantitatively when local structure is strongly coupled.
13127 · Ligand selection
Alter metal composition as an analogue of doping/alloying to tune hybrid band gaps.
Claimed effects: Can shift band gaps, sometimes to intermediate values or with direct variability across composition.
Controlling variables: metal ratio · choice of main-group or transition metal · ordered mixed-metal structure
Representative materials: mixed Cu-Pb iodides · Y/Pb iodide systems · ZnSe/SnSe hybrids
Caveat: Straightforward in principle but difficult in practice; examples are limited.
13126 · Metal selection
Oxidise or chemically dope conductive organic/hybrid stacks to increase carrier density and change insulating or semiconducting states toward metallic behaviour.
Claimed effects: Can raise conductivity in phthalocyanine-type systems and organic semiconductors.
Controlling variables: iodine doping · carrier concentration · redox stability · structural change on oxidation
Representative materials: phthalocyanine CPs · Ni(Pc)(I3)0.33 · Li-doped picene
Caveat: Trapping centres and structural disorder can limit carrier mobility; framework design must tolerate redox changes.
13124 · Metal-organic polymers
Use ammonia, phosphane, amines and diamines to control branching, layer spacing and dimensionality.
Claimed effects: Can tune dimensionality and band gaps, often by structural rather than directly electronic roles.
Controlling variables: NH3 versus PH3 · primary amine chain length · diamine denticity · growth truncation
Representative materials: copper cubane systems · amine-separated perovskites
Caveat: Aliphatic hydrocarbons are mostly inert and insulating; effects are often geometric spacer effects.
13127 · Ligand selection
Fill MOF channels with redox electrolytes or exploit porous frameworks to facilitate ion/electron transport in photoelectrochemical processes.
Claimed effects: Opens reversible oxidation, water oxidation and photochromic ion/electron transport routes.
Controlling variables: pore accessibility · redox electrolyte · metal-centre redox chemistry · oxygen stoichiometry
Representative materials: Zn(II)/Al(III) dicarboxylate frameworks · Fe Basolite MOF · TiO2 dicarboxylate framework
Caveat: These are not necessarily direct solid-state electronic conductivity demonstrations.
13129 · 3D Porous metal organic frameworks
Select metals and ligands to tune orbital overlap, band gap and conductivity across metallic, semiconducting and insulating behaviours.
Claimed effects: Can modulate band gap and conductivity in CPs and hybrids.
Controlling variables: metal identity · ligand pi acidity · donor/acceptor strength · metal-ligand orbital alignment
Representative materials: TTF-M(dmit)2 · phthalocyanine CPs · iodoplumbate hybrids
Caveat: No universal predictive framework; local structure often complicates electronic arguments.
13123 · Metal-organic polymers
These are the review authors’ synthesis, not newly measured results.
One-dimensional coordination polymers are presented as benchmark systems for understanding non-covalent interactions that underlie conductive hybrid materials.
Evidence basis: multi_reference
Caveat: Restricted dimensionality makes them simpler but not necessarily directly device-relevant.
13123 · Metal-organic polymers
Only a few 3D coordination polymers, mainly Cu or Ag containing, had low but measurable conductivities in the 10^-9 to 10^-3 S cm^-1 range by this review.
Evidence basis: single_reference
Caveat: This is a review-level range and not a complete primary database.
13128 · 3D Porous metal organic frameworks
Aromatic organic components are promising hybrid-semiconductor ligands because they can be semiconducting themselves, rigid and self-assembling.
Evidence basis: multi_reference
Caveat: The review also says the many design variables make their effects hard to isolate.
13127 · Ligand selection
In coordination polymers, targeted metal and ligand selection can tune conductivity and band gap across metallic, semiconducting and insulating regimes.
Evidence basis: multi_reference
Caveat: The review later stresses that no transparent universal design rules exist.
13123 · Metal-organic polymers
Charged point defects can generate electron and hole carriers in both organic and inorganic semiconductors, complicating simple intrinsic-band-gap interpretations.
Evidence basis: single_reference
Caveat: Defect identity and concentration remain material-specific.
13122 · Organic semiconductors
The review finds no empirical evidence that metal coordination geometry alone dictates electronic trends in 2D hybrids.
Evidence basis: review_reasoning
Caveat: Local geometry still matters structurally; the claim is about absence of a simple electronic rule.
13126 · Structural motifs
A grand challenge is to establish transparent structure-property-composition design principles for conductive hybrid frameworks.
Evidence basis: review_reasoning
Caveat: The proposed computational route was prospective, not a completed design framework.
13129 · Conclusions and challenges
High-quality inorganic semiconductors provide much higher mobility and conductivity benchmarks than most hybrid frameworks, setting the aspirational performance target.
Evidence basis: single_reference
Caveat: Benchmarks are context values from a data handbook, not review measurements.
13121 · Inorganic semiconductors
Large main-group elements such as Sn, Pb and Bi are emphasised as highly tunable in hybrid networks, ranging from metallic to insulating depending on ligand selection.
Evidence basis: multi_reference
Caveat: Tunability is broad and ligand-dependent rather than a reliable design law.
13126 · Structural motifs
MOF-5 is a cautionary example: it has reported optical/calculated band gaps, but the review found no solid-state conductivity measurements and flat calculated bands consistent with localised carriers.
Evidence basis: multi_reference
Caveat: Statement is limited to evidence available to the 2012 review.
13128 · 3D Porous metal organic frameworks
The Mott insulator-to-metal transition should be theoretically possible in semiconducting metal-organic frameworks, but had not yet been observed by this review.
Evidence basis: review_reasoning
Caveat: This is theoretical extrapolation from inorganic/organic semiconductor physics to hybrid frameworks.
13120 · Abstract
Robust n-type organic channels remain difficult because high electron affinity aids n-type transport but tends to make compounds unstable to oxygen and moisture.
Evidence basis: multi_reference
Caveat: Perylene derivatives are highlighted as promising but not yet broadly adapted into hybrids.
13125 · Metal-organic polymers
Despite progress in 1D, 2D and 3D hybrid systems that absorb light and conduct electricity, the review found no evidence for direct applications in high-efficiency photochemical or electrochemical devices.
Evidence basis: review_reasoning
Caveat: Reflects status at publication in 2012.
13129 · Conclusions and challenges
Pure electronic or molecular-orbital arguments are insufficient for quantitative design of hybrid band gaps because local structure is intimately coupled to electronic behaviour.
Evidence basis: multi_reference
Caveat: The review supports qualitative trends but warns against simple quantitative transfer.
13127 · Ligand selection
Organic semiconductors more often involve localised carriers, low dielectric screening and thermally activated hopping or tunnelling rather than purely delocalised band transport.
Evidence basis: single_reference
Caveat: Doping can drive some organic systems metallic, so localisation is not universal.
13122 · Organic semiconductors
Peripheral S-S contacts in TTF-M(dmit)2 systems create a 2D network that can avoid the Peierls instability typical of one-dimensional molecular metals.
Evidence basis: single_reference
Caveat: Interpretation is specific to sulfur-rich donor-acceptor stacks and should not be generalised to all CPs.
13123 · Metal-organic polymers
Ru(II) and Os(II) are described as favourable for conductive coordination polymers because their valence electrons can delocalise across bridging ligands without major coordination-sphere changes on oxidation.
Evidence basis: single_reference
Caveat: Applies to specific phthalocyanine/bridged systems, not all Ru/Os frameworks.
13124 · Metal-organic polymers
Many reported semiconducting frameworks have been classified mainly from optical band-gap magnitudes, which is insufficient evidence for charge transport or stability of carriers.
Evidence basis: review_reasoning
Caveat: The review does not deny semiconducting behaviour, but argues direct transport evidence is needed.
13121 · Introduction
Every row remains visibly secondary and links to a primary dossier only where the mapping is verified.
| Material | Property | Reported value | Context and quality | Primary evidence | Review source |
|---|---|---|---|---|---|
| Secondary3D coordination polymers mainly containing Cu or Ag | electrical conductivity | 10^-9 to 10^-3 S cm-1 | review-level range for few 3D CP examples; value_numeric records lower bound Text · Range | No verified corpus mapping | 13128 · 3D Porous metal organic frameworks |
| SecondaryBC4B and BC6B terthiophene derivatives | carrier mobility | mu = 1.6 x 10^-2 and 1.4 x 10^-2 cm2 V-1 s-1 | modified molecule A derivatives; value_numeric records BC4B Caption · Range | No verified corpus mapping | 13126 · Beyond 1D · Fig. 10 |
| SecondaryCopper based 0D clustered systems | band gap | 1.67 eV to 3.68 eV | dependent on ligand selection; value_numeric records lower bound Text · Range | No verified corpus mapping | 13126 · Structural motifs |
| SecondaryCu[Cu(pdt)2] | electrical conductivity | approaches 10^-3 S cm-1 | room temperature Text · Approximate | No verified corpus mapping | 13129 · 3D Porous metal organic frameworks |
| SecondaryCu(TCNQ) | electrical conductivity | 0.25 S cm-1 to 1.3 x 10^-5 S cm-1 | room temperature; two polymorphs Text · Range | No verified corpus mapping | 13123 · Metal-organic polymers |
| Secondary(DCNQI)2Cu | electrical conductivity | ca. 800 S cm-1 at room temperature to 5 x 10^5 S cm-1 at 3.5 K | molecular metal; value_numeric records room-temperature value Text · Range | No verified corpus mapping | 13124 · Metal-organic polymers |
| SecondaryInSb | carrier mobility | 7 x 10^4 cm2 V-1 s-1 | high-quality inorganic material baseline Text · Exact Reported | No verified corpus mapping | 13121 · Inorganic semiconductors |
| SecondaryIodine-doped phthalocyanine coordination polymers | electrical conductivity | 1 x 10^-6 to 2 x 10^-1 S cm-1 | iodine-doped compounds; value_numeric records upper end Text · Range | No verified corpus mapping | 13124 · Metal-organic polymers |
| SecondaryIodoplumbate systems | band gap | 2.2 eV to 4.0 eV | halide/iodoplumbate family; value_numeric records lower bound Text · Range | No verified corpus mapping | 13127 · Ligand selection |
| SecondaryMOF-5 | calculated band gap | 3.4 eV | PBE density functional calculation Text · Exact Reported | No verified corpus mapping | 13128 · 3D Porous metal organic frameworks |
| SecondaryMOF-5 | band gap | B3.5 eV | reported for MOF-5 structure in Fig. 16 Text · Approximate | No verified corpus mapping | 13128 · 3D Porous metal organic frameworks |
| SecondaryNi(Pc)(I3)0.33 | electrical conductivity | B500 S cm-1 at room temperature to 5000 S cm-1 at 20 K | value_numeric records room-temperature value Text · Approximate | No verified corpus mapping | 13124 · Metal-organic polymers |
| SecondaryPentacene | hole mobility | as high as 35 cm2 V-1 s-1 | room temperature Text · Approximate | No verified corpus mapping | 13122 · Organic semiconductors |
| SecondaryPTCDI-TFB | carrier mobility | mu = 1.7 x 10^-2 cm2 V-1 s-1 | n-type perylene derivative; air-stability context Text · Exact Reported | No verified corpus mapping | 13125 · Metal-organic polymers |
| SecondaryTTF-[Ni(dmit)2] | electrical conductivity | sigma B 1.5 x 10^5 S cm-1 | down to at least 4 K; increased low-temperature conductivity Text · Approximate | No verified corpus mapping | 13123 · Metal-organic polymers |
| SecondaryTTF-[Ni(dmit)2] | electrical conductivity | ca. 300 S cm-1 | room temperature; metallic behaviour Text · Approximate | No verified corpus mapping | 13123 · Metal-organic polymers |
| SecondaryTTF-TCNQ | electrical conductivity | sigma = 1.5 x 10^4 S cm-1 | maximum conductivity; metallic above 60 K Text · Exact Reported | No verified corpus mapping | 13123 · Metal-organic polymers |
| SecondaryUndoped pi-conjugated polymers | carrier concentration | up to 10^17 cm-3 | undoped polymers; review attributes carriers to defects Text · Approximate | No verified corpus mapping | 13122 · Organic semiconductors |
| Secondary[Y(DMSO)jPbkIl] system | band-gap variability | B0.8 eV | differing quantities of Y and Pb Text · Approximate | No verified corpus mapping | 13126 · Metal selection |
| SecondaryZnO | carrier mobility | 150 cm2 V-1 s-1 | high-quality inorganic material baseline Text · Exact Reported | No verified corpus mapping | 13121 · Inorganic semiconductors |
Open questions are presented as review-author priorities, not conclusions from the primary database.
Aromatic and conjugated ligand effects are difficult to isolate because too many structural and electronic variables change together.
Proposed direction: Develop methodical ligand series for controlled comparison.
13128 · Ligand selection
Some prominent frameworks, especially MOF-5, were called semiconductors without direct solid-state conductivity measurements.
Proposed direction: Separate optical/photoelectrochemical band-gap evidence from direct electrical transport measurements.
13128 · 3D Porous metal organic frameworks
The review found no direct evidence for high-efficiency photochemical or electrochemical device applications of these hybrid systems.
Proposed direction: Progress from fundamental properties to thin films, device integration and manufacturing.
13129 · Conclusions and challenges
There was very little information on how ligand choice controls photoactive and electronic effects in hybrid networks.
Proposed direction: Systematically vary ligand families while holding metal/topology constant where possible.
13125 · Beyond 1D
Simple molecular-orbital trends fail quantitatively because local structure strongly affects band gaps and transport.
Proposed direction: Combine structural characterisation with calculations and transport measurements instead of using orbital arguments alone.
13127 · Ligand selection
Hybrid framework unit cells and structural complexity make predictive modelling a significant task.
Proposed direction: Use high-performance computing and targeted electronic-structure workflows for realistic frameworks.
13130 · Conclusions and challenges
A Mott insulator-to-metal transition in semiconducting MOFs was theoretically plausible but unobserved.
Proposed direction: Design dopable frameworks with sufficient band curvature and controllable carrier concentration.
13120 · Abstract
Robust n-type organic channels are difficult because high-electron-affinity molecules can be oxygen- and moisture-sensitive.
Proposed direction: Target stable perylene or related high-EA ligands and test their incorporation into hybrids.
13125 · Metal-organic polymers
Computationally stable ligand/framework targets may be synthetically implausible, as noted for hexa-substituted benzene examples.
Proposed direction: Screen targets for synthetic accessibility as well as electronic stability.
13127 · Ligand selection
No systematic approach was established for designing hybrid frameworks with targeted electronic or optical properties.
Proposed direction: Develop transparent metal/ligand/topology rules supported by electronic-structure modelling and experiment.
13120 · Abstract
Mappings show which printed review references have a verified counterpart in the frozen primary corpus.
| Reference | Study | Role and context | Corpus mapping |
|---|---|---|---|
| Ref. 102006 | Title unavailable | taxonomy · dimensionalitySource for ImOn dimensionality notation used to classify inorganic and organic framework dimensionality. | Unmapped |
| Ref. 182001 | Title unavailable | photovoltaic_contextCited for the photovoltaic/photoelectrochemical framing of semiconductor excitation and carrier extraction. | Unmapped |
| Ref. 222004 | Title unavailable | transport_benchmarkReference for benchmark mobility, carrier concentration and conductivity ranges in inorganic semiconductors. | Unmapped |
| Ref. 331961 | Title unavailable | transport_mechanismOriginal Mott metal-insulator-transition reference invoked for critical carrier concentration. | Unmapped |
| Ref. 341978 | Title unavailable | transport_mechanismRefinement and validation context for the Mott criterion across inorganic semiconductors. | Unmapped |
| Ref. 362004 | Title unavailable | transport_benchmarkBenchmark organic semiconductor hole mobility cited by the review. | Unmapped |
| Ref. 402010 | Title unavailable | transport_mechanismOrganic example of extrinsic doping past a Mott-like transition into metallic and superconducting behaviour. | Unmapped |
| Ref. 432009 | Title unavailable | transport_benchmarkCited for high carrier concentrations in nominally undoped conjugated polymers. | Unmapped |
| Ref. 471990 | Title unavailable | transport_benchmark · metal_organic_polymersCited for a phthalocyanine polymer conductivity benchmark. | Unmapped |
| Ref. 482011 | Title unavailable | taxonomy · historical_contextRecent review used for Fig. 2 topology taxonomy and publication-growth context for metal-organic polymers. | Unmapped |
| Ref. 492012 | Title unavailable | material_family · transport_benchmarkCited for higher-dimensional conductive coordination polymers and low but measurable 3D framework conductivities. | Unmapped |
| Ref. 571973 | Title unavailable | transport_benchmarkOne of the cited original charge-transfer-salt references for TTF-TCNQ metallic conductivity. | Unmapped |
| Ref. 581953 | Title unavailable | transport_mechanismCited for Peierls distortion/transition interpretation in one-dimensional charge-transfer conductors. | Unmapped |
| Ref. 591986 | Title unavailable | transport_benchmark · material_familyOriginal hybrid TTF-M(dmit)2 coordination-polymer study used for conductivity and Peierls-avoidance discussion. | Unmapped |
| Ref. 631999 | Title unavailable | transport_benchmarkCited for Cu-TCNQ polymorph and conductivity comparison. | Unmapped |
| Ref. 642004 | Title unavailable | transport_benchmarkReference used for the molecular-metal DCNQI-Cu conductivity benchmark. | Unmapped |
| Ref. 681988 | Title unavailable | transport_benchmark · structure_propertyCited for metal/ligand-acidity trends and iodine-doped phthalocyanine CP conductivity range. | Unmapped |
| Ref. 762006 | Title unavailable | structure_propertyCited as an Ag-Ag contact example with a short Ag-Ag distance relevant to conductive network formation. | Unmapped |
| Ref. 862010 | Title unavailable | transport_benchmark · ligand_designCited in Fig. 10 for modified n-type terthiophene molecules with reported carrier mobilities. | Unmapped |
| Ref. 942007 | Title unavailable | transport_benchmark · ligand_designCited for the PTCDI-TFB n-type organic ligand mobility benchmark. | Unmapped |
| Ref. 962008 | Title unavailable | ligand_designCited for the original difluorodioxocyclopentene-annelated terthiophene structure in Fig. 10. | Unmapped |
| Ref. 1062008 | Title unavailable | material_family · ligand_designCited for a lead benzene hexathiolate hybrid using a chalcogen-terminated aromatic ligand. | Unmapped |
| Ref. 1082009 | Title unavailable | bandgap_benchmark · ligand_selectionCited for iodoplumbate band-gap variability and halide-selection discussion. | Unmapped |
| Ref. 1111991 | Title unavailable | ligand_selection · structure_propertyCited for halide substitution and layer-spacing effects in hybrid perovskite-like structures. | Unmapped |
| Ref. 1122010 | Title unavailable | material_family · structure_propertyCited as the authors' ongoing/recent cubic lead-centred 3D hybrid example. | Unmapped |
| Ref. 1222008 | Title unavailable | bandgap_benchmark · metal_selectionCited for mixed Y/Pb composition causing direct band-gap variability. | Unmapped |
| Ref. 1272009 | Title unavailable | material_family · ligand_designCited for blending ZnSe/SnSe and using a cationic species as counter-ion/spacer in layered hybrids. | Unmapped |
| Ref. 1302004 | Title unavailable | bandgap_benchmark · ligand_selectionCited for ligand-dependent band gaps and ammonia/phosphane effects in copper cubane systems. | Unmapped |
| Ref. 1352006 | Title unavailable | structure_property · ligand_selectionCited for chalcogen-size/band-gap trends in hybrid materials. | Unmapped |
| Ref. 1392008 | Title unavailable | ligand_design · research_gapCited for an unusual tetrahedral carbon-centred ligand system whose conductivity was not reported. | Unmapped |
| Ref. 1442008 | Title unavailable | bandgap_benchmarkCited for the approximately 3.5 eV reported MOF-5 band gap. | Unmapped |
| Ref. 1462010 | Title unavailable | bandgap_benchmark · modellingCited for calculated MOF-5 band gap and band-structure assessment. | Unmapped |
| Ref. 1472004 | Title unavailable | measurement_interpretationCited for the interpretation that MOF-5 electronic transitions are ligand-to-metal charge transfer, not direct organic-ligand transport. | Unmapped |
| Ref. 1512008 | Title unavailable | transport_benchmarkCited for conductivity of a Cu-based thiophene framework. | Unmapped |
| Ref. 1522010 | Title unavailable | transport_benchmarkCited for comparable conductivity in a mixed metal Cu-Ni thiophene framework. | research_0203 |
| Ref. 1552009 | Title unavailable | photochromism · ion_electron_transportCited for a photochromic TiO2-centred framework where porosity facilitates ion and electron transport. | Unmapped |
| Ref. 1572011 | Title unavailable | outlook · device_roadmapCited for a roadmap from fundamental properties through thin films, device integration and manufacturing. | Unmapped |
| Ref. 1582011 | Title unavailable | outlook · analogyCited as an analogy for mobile electrons emerging in materials previously viewed as inert. | Unmapped |