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The synthesis, crystal structures, and electronic band structure calculations, integrated with in-depth electron spin resonance and static susceptibility, dc conductivity, and (super 1)H spin-lattice relaxation studies of (EDT-TTF-CONH2)(sub 6)[Re6Se8(CN)(sub 6)] whose Kagome topology is unprecedented for any TTF-based materials are described.

The ability of I...I van der Waals interactions to direct the self-assembly of slabs of the radical cation of ethylenedithio-1,2-dilodo-tetrathiafulvalene, EDT-TTF-I2, and polymeric lead iodide covalent anionic layers is demonstrated by the synthesis of single crystals of beta-(EDT-TTF-I2)(sub 2)(super .+)[(Pb(sub 5/6)square(sub 1/6)I2)(super 1/3)](sub 3). A complementary, commensurate pattern of association is revealed at the organic-inorganic interface.

A novel method of synthesizing {AcrH}{Ni(dmit)(sub 2)}(sub 3) and {PheH}{Ni(dmit)(sub 2)}(sub 3) was developed as well as their structures were determined through x-ray crystallography. Results have shown that the crystal structures of the two compounds were very distinct from each other. The former compound exhibited metallic conductivity behavior, while the latter displayed a semimetallic conductivity behavior.

A study was done on the neutral molecular component site along the series of metallic organic-inorganic solvates. The series of single crystals composed of a monoanion which is a hexanuclear chalcohalide rhenium cluster and the neutral guest molecules are dimethylformamide. The compounds possess similar basic structural organization in which conducting organic cation radical slabs are sandwiched by inorganic cluster monoanion layers.

A single component molecular conductor is isolated from electrocrystallization of the monoanionic gold bis(dithiolene) complex based on the N-ethyl-1,3-thiazoline-2-thione-4,5-dithiolate (Et-thiazdt) ligand. First-principles density functional theory (DFT) calculations have shown that the ground state is antiferromagnetic with a very small band gap.

A series of two dimensional (2D) metals is shown to have one single [beta]-slab layered topology despite successive increases of the cluster anion negative charge. The BDT-TTP salts have provided a series of materials with strongly related but slightly different Fermi surfaces.

A first complete series of racemic and enantiopure conducting salts are synthesized and characterized with metallic character, based on chiral oxazolines. Despite strongly related crystalline and electronic structures, the higher conductivity of pure enantiomers, lacking the disorder inherent to racemic mixture, demonstrates that the chiral donor route is very promising for the elaboration of other metallic salts.

The deliberate design of a series of single crystals for conducting two-dimensional radical cation salts of o-bis(amide)-appended ethylenedithiotetrathiafulvalene, beta'-[EDT-TTF-(CONH2)2]2X (X = HSO(sub 4)(super -1), ClO(sub 4)(super -1), ReO(sub 4)(super -1)or AsF(sub 6)(super -1) and of their parent monocomponent solid EDT-TTF-(CONH2)2 is discussed. A recurrent, puckered ribbon constructed out of self-complementary, hydrogen-bonded amide...amide ring motifs is an important design element.

BOOK REVIEW Surfactants and Polymers in Drug Delivery. Drugs and the Pharmaceutical Sciences. Volume 122 by Malmsten, Martin

Enantiopure (S,S) and (R,R) dimethyl-ethylenedithio-tetrathiafulvalene (DM-EDT-TTF) 1 donors are synthesized by cross coupling followed by decarboxylation reactions. In the solid state the methyl groups are arranged in axial positions within sofa-type conformation for the six-membered rings. Crystalline radical cation salts formulated as [(S,S)-1]2PF6, [(R,R)-1]2PF6, and [(rac)-1]2PF6 are obtained by electrocrystallization. When the experiment is conducted with enantioenriched mixtures both enantiopure and racemic phases are obtained. The monoclinic enantiopure salts, containing four independent donors in the unit cell, show semiconducting behavior supported by band structure calculations of extended Hückel type. The racemic salt contains only one independent donor in the mixed valence oxidation state +0.5. Under ambient pressure the racemic material is metallic down to 120 K, while an applied pressure of 11.5 kbar completely suppresses the metal-insulator transition. Band structure calculations yield an open Fermi surface, typical for a pseudo-one-dimensional metal, with unperfected nesting, thus ruling out the possibility of charge or spin density modulations to be at the origin of the transition. Raman spectroscopy measurements, in agreement with structural analysis at 100 K, show no indication of low-temperature charge ordering in the racemic material at ambient pressure, thus suggesting Mott-type charge localization for the observed metal-insulator transition. [ABSTRACT FROM AUTHOR]

The electrocrystallization of diiodo- and dibromo-ethylenedithiotetrathiafuvalene (EDT-TTFI[sub2] and EDT-TTFBr[sub2]) in the presence of the polymeric 1D [Et[sub4]N][Cd(SCN)[sub3]] as an electrolyte affords two different salts, formulated as [EDT-TTF-I[sub2]][sub4][Cd[sub3](NCS)[sub8]] • CH3CN H[sub2]O (1) and [EDT-TTF-Br[sub2]][sub10][Cd[sub5](SCN)[sub14]] • 2TCE (2), characterized by a two- dimensional segregation of the partially oxidized donor molecules and the polymeric anionic network incorporating embedded solvent molecules. Both salts exhibit a partial charge transfer, that is, p = 0.5 in 1 and an unconventional p = 0.4 in 2. They behave as semiconductors with σ[subRT] = 0.67 and 33 S cm[sup-1] and activation energies of 330 and 370 K for 1 and 2, respectively. Compared with a 1:3 Cd/SCN ratio of the starting electrolyte, the reconstructed, thiocyanate (SCN)-deficient motifs [Cd[sub3](NCS)[sub8]][sub2] and [Cd[sub5](SCN)[sub14]][sub4] organize into layered hollow structures with cavities filled by solvent molecules, halogen-bonded to the halogenated TTF molecules, through a C[subTTF]—N≡C—CH[sub3] interaction in 1, through a type II C[subTTF]—Br⋯CI-CTCE halogen/halogen interaction in 2. Band structure and Fermi surface calculations for the two salts indicate a two-dimensional character, while the semiconducting properties of the salts are attributed to an efficient nesting of the hidden 1D Fermi surfaces. [ABSTRACT FROM AUTHOR]

A series of 2D metals, β-(BDT-UP)6[Re6Se6Cl8]·(CHCl2-CHCl2)2, 2; β-(ST-UP)6[Re6S6Cl8]·(CH2-Cl-CHCl2)2, 3; β-(BDT-UP)7[Re6S6Cl8]0.5[Re6S7Cl7]0.5·(CH2Cl2), 4; β-(BDT-UP)7[Re6Se6Cl8]0.5[Re6S7- Cl7]0.5(CH2Cl2), 5; β-(BDT-UP)8[Re6S7Cl7]·(CH2Cl2)4, 6 (BDT-TTP and ST-UP are 2,5-bis(1,3-dithiol-2- ylidene)-1,3,4,6-tetrathiapentalene and 2-(1,3-diselenol-2-ylidene)-5(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene, respectively) is reported to have one single β-slab layered topology despite successive increases of the cluster anion negative charge. The charge density within the templating composite inorganic-neutral molecule slab is shown to remain above a threshold of ca. one negative charge per square nanometer, that is, for cluster anions with two negative charges and higher. Conversely, discrete stacks are shown to be stabilized instead in the semiconducting salts (BDT-TTP)2[Re6S5Cl9], 1 where the cluster anion bears one negative charge only. The electronic structure of salts 2-6 is shown to be very stable and kept almost intact across the series. The templating strategy is shown to fulfill its anticipated potential for deliberate installment of incommensurate band fillings in molecular metals. The deliberate admixture of the 6:1 and 8:1 structures yields novel phases with a 7:1 stoichiometry with the anticipated crystal and electronic structures. The action at the organic-inorganic interface triggered by changing the anion charge yet keeping its shape and volume identical, which ultimately governs the shape of the unit cell, is of paramount importance in defining the Fermi surface of these metallic salts. The present BDT-UP salts thus provide a series of materials with strongly related but subtly different Fermi surfaces worthy of many physical studies. Shubnikov-de Haas measurements are expected to be particularly interesting since they are especially sensitive to the details of the Fermi surface. [ABSTRACT FROM AUTHOR]

(EDT-TTF-CONH2)6[Re6Se8(CN)6], space group R..., was prepared by electrocrystallization from the primary amide-functionalized ethylenedithiotetrathiafulvalene, EDT-TTF-CONH2 (E½1 = 0.49 V vs SCE in CH3CN), and the molecular cluster tetraanion, [Re6Se8(CN)6]4- (E½ = 0.33 V vs SCE in CH3CN), equipped with hydrogen bond donor and hydrogen bond acceptor functionalities, respectively. Its Kagome topology is unprecedented for any TTF-based materials. The metallic state observed at room temperature has a strong two-dimensional character, in coherence with the Kagome lattice symmetry, and the presence of minute amounts of [Re6Se8(CN)6](3-)· identified by electron spin spectroscopy. A structural instability toward a distorted form of the Kagome topology of lesser symmetry is observed at ca. 180 K. The low-temperature structure is associated with a localized, electrically insulating electronic ground state and its magnetic susceptibility accounted for by a model of uniform chains of localized S = ½ spins in agreement with the 100 K triclinic crystal structure and band structure calculations. A sliding motion, within one out of the three (EDT-TTF-CONH2)2 dimers coupled to the [Re6Se8(CN6)(3-)·]/[Re6Se8(CN6)4-] proportion at any temperature, and the electronic ground state of the organic-inorganic hybrid material are analyzed on the basis of ESR, dc conductivity, ¹H spin-lattice relaxation, and static susceptibility data which qualify a Mon localization in [EDT-TTF-CONH2]6[Re6Se8(CN)6]. The coupling between the metal-insulator transition and a structural transition allows for the lifting of a degeneracy due to the ternary axis in the high temperature, strongly correlated metallic phase which, in turn, leads to Heisenberg chains at low temperature. [ABSTRACT FROM AUTHOR]

Studies the deliberate design of a series of single crystals of conducting two-dimensional radical cation salts of o-bis(amide)-appended ethylenedithiotetrathiafulvalene and of their parent monocomponent solid ethylenedithiotetrathiafulvalene. Presence of a robust and adaptable hydrogen bond network in single-component solids; Preservation of the slab topology in radical cation salts; Restoration of an organic-inorganic interface.

The ability of I···I van der Waals interactions to direct the self-assembly of slabs of the radical cation of ethylenedithio-1,2-diiodo-tetrathiafulvalene, EDT-TTF-I[sub 2], and polymeric lead iodide covalent anionic layers is demonstrated by the synthesis of single crystals of β-(EDT-TFF-I[sub 2])[sub 2, sup •+][(Pb[sub 5/6...1/6]I[sub 2])[sup 1/3-]][sub 3], triclinic, P-1, a = 7.7818(8), b = 7.9760(8), c = 19.9668(2) Å, α = 82.409(12), β = 85.964(12), γ = 61.621(11)°, V = 1080.76(19) ų, R1, wR2 = 0.0459, 0.0947; and β-(EDT-TTF-I[sub 2])[sub 2, sup •+][(Pb[sub 2/3+x]Ag[sub 1/3-2x...x] I[sub 2])[sup 1/3]][sub 3], x ≈ 0.05, triclinic, P-1, a = 7.7744(8), b = 7.9193(8), c = 19.834(2) Å, α = 87.189(12), β = 83.534(12), γ = 61.602(11)°, V = 1067.4(2) ų, R1, wR2 = 0.0508, 0.0997. The state-of-the-art, combined microprobe and structural analysis of the metal site vacancies and occupancies patterns reveal a commensurate organic-inorganic interface and point out the importance of halogen···halogen van der Waals interactions to future studies aiming at directing interface topologies. The electronic structure, room-temperature metallic character and metal-insulator transition at ca. 70 K of the two-dimensional organic slabs are retained upon alloying of the inorganic sublattice with monocations. The room-temperature conductivity of the metallic lead-silver alloy is 2 orders of magnitude larger than that of β-(EDT-TTF-I[sub 2])[sub 2, sup •+][(Pb[sub 5/6...1/6]I[sub 2])[sup 1/3-]][sub 3]. This calls for the study of materials with diverse alloying patterns with metal cations of different nature and charge. [ABSTRACT FROM AUTHOR]

The article discusses the syntheses, structure and properties of chiral molecular metals. Within the extended series of organic metals and superconductors based on tetrathiafulvalene (TTF) and derivatives, the introduction of chirality offers an invaluable opportunity to evaluate the role of disorder on the conductive properties since radical cation salts of enantiopure donors are expected to suffer less from structural disorder than those of racemates, where the crystal structure may tolerate the enantiomers exchanging places.

We report structural, transport, and optical properties and electronic structure calculations of the δ'-(BEDT-TTF) 2 CF 3 CF 2 SO 3 (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene) organic conductor that has been synthesized by electrocrystallization. Electronic structure calculations demonstrate the quasi-one-dimensional Fermi surfaces of the compound, while the optical spectra are characteristic for a dimer-Mott insulator. The single-crystal X-ray diffraction measurements reveal the structural phase transition at 200 K from the ambient-temperature monoclinic P 2 1 / m phase to the low-temperature orthorhombic Pca 2 1 phase, while the resistivity measurements clearly show the first order semiconductor-semiconductor transition at the same temperature. This transition is accompanied by charge-ordering as it is confirmed by splitting of charge-sensitive vibrational modes observed in the Raman and infrared spectra. The horizontal stripe charge-order pattern is suggested based on the crystal structure, band structure calculations, and optical spectra., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Molecular metals have been essentially obtained with tetrathiafulvalene (TTF)-based precursors, either with multicomponent ionic materials or, in a few instances, with single-component systems. In that respect, gold bis(dithiolene) complexes, in their neutral radical state, provide a prototype platform toward such single-component conductors. Herein we report the first single-component molecular metal under ambient pressure derived from such Au complexes without any TTF backbone. This complex exhibits a conductivity of 750 S·cm -1 at 300 K up to 3800 S·cm -1 at 4 K. First-principles electronic structure calculations show that the striking stability of the metallic state finds its origin in sizable internal electron transfer from the SOMO-1 to the SOMO of the complex as well as in substantial interstack and interlayer interactions.

Radical cation salts composed of a bis(ethylenedithio)tetrathiafulvalene (ET) donor with homo-/heterosubstituted Cl/CN anilic acids as purely organic molecular conducting materials formulated as [BEDT-TTF] 2 [HClCNAn] (1) and [BEDT-TTF][HCl 2 An] (2) have been prepared by electrocrystallization. Compounds 1 and 2 crystallized in the monoclinic space group P2/c for 1 and I2/a for 2, showing segregated donor-anion layers arranged in a α'-type donor packing pattern (1) and twisted parallel columns (2), respectively. Single-crystal conductivity measurements show that 1 is a semiconductor with room-temperature conductivity of 10 -2 S cm -1 and an activation energy E a of 1900 K.

Control of band filling or doping of molecular (semi)conductors can be performed by substitutional insertion of molecules with a similar shape but a different electron count, with one more or one less electron. This strategy has been explored here within the semiconducting, single-component, radical gold dithiolene complex [AuOC4] bearing para-butoxyphenyl substituents. Alloying with the corresponding neutral nickel dithiolene complex [NiOC4] lacking one electron afforded a complete isostructural series [NiOC4]1-x[AuOC4]x, spanning the whole composition range from x = 0 to x = 1 by 0.1 increments, further characterized by X-ray diffraction and EDX analyses. Magnetic susceptibility data confirm the antiferromagnetic interactions between neighboring radical gold dithiolene complexes. The electrical conductivity increases exponentially with the x gold fraction, while the activation energy remains constant in the more conducting, gold-rich samples. This behavior is tentatively assigned to the tunneling barriers of variable width (with x) but of constant height, separating more conducting gold-rich segments. Comparison of redox potentials for the 1e(-) oxidation and reduction of both [NiOC4] and [AuOC4] dithiolene complexes indicates that the [NiOC4] nickel complex does not act as a dopant for the radical [AuOC4] complex.

The search for hybrid organic-inorganic materials, which have the great advantage that they can be synthesized at moderate temperature (T < 200 °C), remains a great challenge in the field of ferroelectrics. Here, a room-temperature ferroelectric material with interesting characteristics, (MV)[BiI(3)Cl(2)] (MV(2+) = methylviologen), is reported. Its structure is based on polar inorganic chains resulting from a remarkable Cl/I segregation induced by methylviologen entities, which coincide with the fourfold polar axis of the tetragonal structure. Of great importance is that this room-temperature hybrid ferroelectric displays a clear electrical hysteresis loop with a large spontaneous polarization (>15 μC·cm(-2)).