Electrostatic versus van der Waals Interactions in an n-Type Semiconducting Dianionic Naphthalenediimide Derivative with C_nH_2n+1NH₃⁺ (n = 1–16)

Abstract

Dianionic bis(benzenesulfonate)-naphthalenediimide (BSNDI 2− ) formed simple 2:1 cation−anion salts (Cn-BSNDIs) by the combination of two molar alkylammonium (C n H 2n+1 NH 3 + ) in which the alkyl-chain length (n) was systematically changed from 1 to 16 to study the n-dependent phase transition behavior, molecular assembly structure, dielectric response, and transient conductivity of a series of Cn-BSNDI salts. The electrostatic cation−anion and van der Waals interactions in the molecular assembly compensated for each other, where the elongation of the −C n H 2n+1 chain increased the energy contribution from van der Waals interactions. The crystal lattices of short-chain Cn-BSNDIs (n = 1−4) were rigid and static without temperature-and frequency-dependent dielectric responses. By contrast, large dielectric responses were observed in Cn-BSNDI salts with intermediate n = 5−8 because of the motional freedom of the cation−anion arrangement and thermal fluctuation of the flexible alkyl chains. In the case of Cn-BSNDIs with n = 9−16, the thermal fluctuation of long alkyl chains primarily contributed to the dielectric responses. The one-dimensional intermolecular interactions of Cn-BSNDI salts (n = 1 and 2) showed a dimensional crossover to the two-dimensional C3-BSNDI, and the transient conductivity (ϕΣμ) of C3-BSNDI and C4-BSNDI thin films was much larger than those of the other salts. The rigid crystal lattice of Cn-BSNDIs (n = 3 and 4) became dynamic when n ≥ 5, with a successive phase transition and an even−odd effect in the dielectric constants and ϕΣμ values. The observed interplay of van der Waals and electrostatic interaction allows the dynamic tuning of electronic properties with identical molecular cores as represented by their dielectric response and transient conductivity.

Inhibition Role of Solvation on the Selective Extraction of Co(II): Toward Eco-Friendly Separation of Ni and Co

“…Van der Waals and electrostatic interactions were always present in the range 0–10 Å . When the extractant anion and the metal cation were within 0–3 Å and bonded to form the intermediate molecule MA 2 ·6H 2 O, covalent, electrostatic, and van der Waals interactions were involved. , Therefore, two possible dehydration sites existed at distances of 0–3 and 3–10 Å. The reaction process and the proposed path are shown in Figures S10 and c, respectively.…”

“…42 When the extractant anion and the metal cation were within 0−3 Å and bonded to form the intermediate molecule MA 2 •6H 2 O, covalent, electrostatic, and van der Waals interactions were involved. 43,44 Therefore, two possible dehydration sites existed at distances of 0−3 and 3− ESI−MS was used to analyze the loaded organic phase. According to the results shown in Figure 7, the isotopic peak centered at m/z 323.23 can be assigned to (HA)H + , and the most intense peak at m/z 645.46 can be attributed to (HA) 2 H + .…”

Nucleophilic aromatic substitution approach to phosphanyl-substituted diboraanthracenes: biphilic compounds with tunable electron affinities

“…While the polycationic charge of the obtained compounds undoubtedly contributes substantially to their Lewis acidity, it also creates salt-like species. Although these may have some potential for applications in the fabrication of optoelectronic devices, 12 Ph 2 P(S)-DBAs are our current favorites due to their better synthetic accessibility.…”

Carrier Transport Switching of Ferroelectric BTBT Derivative

“…Organic semiconductors have been intensively studied as active layers for next-generation wearable devices. − Molecular assemblies of low-molecular-weight π-molecules in active layers tend to have lower thermal stability, chemical stability, and carrier mobility than inorganic semiconducting materials because of their weak intermolecular interactions, such as van der Waals and dipole–dipole interactions. Although some organic semiconductors with strong intermolecular interactions, such as hydrogen bonding and electrostatic interactions, have been reported to overcome such material designing problems, − the introduction of strong intermolecular interactions often disturbs the effective π-stacking structure, reducing the dimensionality and bandwidth of the electronic structure. On the contrary, the weak intermolecular interactions have an advantage in forming electronic materials that have solution processability, flexibility, and external stimulus-responsive physical properties. − In molecular materials, the molecular arrangement dominates the electronic structure and reorganization energy, which directly affects carrier mobility.…”