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Domino reaction of benzo[d]thiazole‐2‐methylamine (S1) has been developed in the presence of MnCl2 ⋅ 4H2O, leading to tetrasubstituted pyrrole coordinated dinuclear Mn(II) complex 1 ([MnClP]2, P−=2,3,4,5‐tetrakis(benzo[d]thiazol‐2‐yl)pyrrol‐1‐ide). The reaction process has been studied by assigning a series of intermediates based on time‐dependent mass spectrometry, control experiments, crystallography, and density functional theory (DFT) theoretical calculation. A plausible mechanism involving an unprecedented divergent‐convergent domino sequence has been proposed. Compound S1 could be activated by MnCl2 ⋅ 4H2O via coordination, which divergently produces two intermediates imine II (1‐(benzo[d]thiazol‐2‐yl)‐N‐(benzo[d]thiazol‐2‐ylmethyl)methanimine) and alkene C (1,2‐bis(benzo[d]thiazol‐2‐yl)ethene) through oxidative self‐condensation and free radical coupling followed by elimination, respectively. They could then react with each other convergently via formal [3+2] cycloaddition to give deprotonated tetrasubstituted pyrrole coordinated intermediate [MnClP] after aromatization. Dimerization of [MnClP] produces the final product 1. Three C−C bonds and one C−N bond are formed through this six‐step domino sequence. The corresponding organic skeleton (HP: 2,2′,2′′,2′′′‐(1H‐pyrrole‐2,3,4,5‐tetrayl)tetrakis(benzo[d]thiazole)) has been obtained from 1 and shows a higher fluorescent quantum yield (52 %) than the reported 3,4‐diphenyl substituted analogue 2,2′‐(3,4‐diphenyl‐1H‐pyrrole‐2,5‐diyl)bis(benzo[d]thiazole) (DPB) (42 %). [ABSTRACT FROM AUTHOR]

In order to comparing and explaining the experimental infrared, electronic absorption and emission spectra of tris (4‐methyl‐1‐(1‐methyl‐1H‐benzo [d] imidazol‐2‐yl) −4H‐benzo [d] imidazo[1,5‐a]imidazol‐3‐yl) methyl (L6), density functional theory calculations were performed to systematically study the spectral properties of several species with different electronic states (L6+, L6 and HL6+), as well as the axial substituted derivative with methoxy group (L6‐OCH3). The main peaks in the vibrational, electronic absorption and emission spectra were assigned in detail. Roles of molecular electronic states and axial substitution on the spectral properties are revealed. The calculated spectra are compared with experimental results to distinguish the nature of L6 in crystal and solvent. This work combing experiment and theoretical calculations would be good example for clarifying molecular electronic states and, thus, promising the practice application of such kind of novel molecules. [ABSTRACT FROM AUTHOR]

A new series of luminescent phosphine copper(I) complexes with cyano- and hydroxyl-substituted 2,2′-bipyridine ligands [CuI(bpy(CN)2)(P(PhX)3)2](ClO4) [X = H (1); Me (2); Cl (3)], [CuI(bpy(CN)2)(POP)](ClO4) (4), [CuI(bpy(OH)2)(PPh3)2](ClO4) (5) and [CuI(bpy(OH)2)(POP)](ClO4) (6) have been synthesized and characterized. Three of these complexes have been structurally characterized by using X-ray crystallography. The effect of the attaching –CN and –OH groups at the ortho-positions of bpy ligand was investigated. In CH2Cl2 solution, these complexes show yellow to orange phosphorescence, with the emission maxima not only sensitive to the electronic nature of the bipyridine ligands, but also considerably varied with the modification of phosphine ligands. In addition, these complexes show intense tunable green to yellow emissions in their solid state. To elucidate the electronic structures and transitions of these complexes, density functional theory (DFT) calculations on representative examples revealed that the lowest energy electronic transition associated with these complexes predominantly originates from metal-to-ligand charge transfer transitions (MLCT). [ABSTRACT FROM AUTHOR]

Herein, quasi-square planar CuII(Hmbm)Cl2 (CBC, Hmbm = (1-methyl-1H-benzo[d]imidazol-2-yl)methanol) was arranged in a pseudo orthogonal way to form Cl-bridged chains, and further π…π interactions resulted in distorted hexagonal layers. DFT calculations reveal a bond strength order of Cu–Cl ＞ Cu–O/N > Cu…Cl. ESI-MS data reveal several small fragments from CBC, but oligomeric [CuII2], [CuII3], and [CuII4] for non-zero in-source energies; MS data indicates the occurrence of several chemical processes, viz. splitting of the ligand, oligomerization, and redox reaction of alcohol to aldehyde and CuII to CuI. Gibbs free energies for the fragments were estimated using DFT. The magnetic susceptibility was modeled with the ferromagnetic coupling J(Cu–Cl2a…Cu) = +0.99(30) cm−1 and J′(π…π) = +0.35(16) cm−1 and g = 2.38(2). HF-EPR determined the anisotropic g-values, gx = 2.24, gy = 2.16, and gz = 2.09, and a hyperfine constant of Az = 450 G. DFT calculations from crystal structure data reveal a J(Cu–Cl2a…Cu) of +3.6 at 296 K and +4.1 cm−1 at 90 K that dominates the magnetic properties, whereas J′(π…π) = 0.04 cm−1 is negligibly small. [ABSTRACT FROM AUTHOR]

The bond order and packing ratios in the single-crystal of the two structural polymorphs as well as the detailed electronic structures of the molecular model were studied using density functional theory. The strength of different Mn coordination bonds was analyzed in detail through Mayer bond order. Besides bond length, many other factors such as the orientation of ligand and nature of metal also significantly influence the bond order. Packing ratios calculated using cluster model reveals that packing along b direction in Dimer is more favorable than other directions due to the associated interactions of π-π and Cl...H when packing in this direction. Electronic structure helps explain the formation of Dimer from monomer or direct forming of Chain from ligand/Cl and metal. This would shed light on further understanding the importance of supramolecular interaction on crystal engineering. [ABSTRACT FROM AUTHOR]

• The experimentally proposed position of proton is proved to be not correct. • L6 backbone is more likely to exist in L6+ form instead of radical. • Systematically g tensors calculations for L6 / HL6+ show experimental EPR result is questionable. • L6·HCl·3CH 3 OH crystal reassigned as L6+·Cl−·3CH 3 OH. • Balanced hole/electron reorganization energy/mobility make L6 good ambipolar semiconductor. L6·HCl·3CH 3 OH crystal was assigned as HL6+·Cl−·3CH 3 OH. Calculations on radical L6 , oxidized cation L6+ , reduced anion L6− , and protonated radical HL6+ favour a L6+ nature rather than HL6+. Spin and charge distributions of L6+ explain its stability. Calculated g tensors for L6 and HL6+ of g ⊥ = 2.0031 and g // = 2.0024 correspond well with other carbon radicals such as methyl radical (2.0025). The much larger experimental g tensors of 2.0130 and 2.0105 are questionable. L6 is predicted to be good ambipolar semiconductor with balanced hole and electron mobilities showing potential applications as OLED and solar cell. [ABSTRACT FROM AUTHOR]

Three series of oligomers containing functionalized imide and thiophene rings, namely the acceptor type bisthiazole imide oligomer with different length (PBTzIn , n = 1–8), the donor-acceptor type derivatives by introducing three electron donating thiophene rings into BTzI (PBTzI3Tm , m = 1–4), and derivatives by substituting the two hydrogen of center thiophene in PBTzI3Tm with fluorine (PBTzI3T-2Fm , m = 1–4), were designed based on some experimentally synthesized oligomers to clarify the roles of oligomer length, thiophene donor, and fluorine-substitution on the charge transfer properties. The charge transfer properties of these imide-functionalized thiazole-based oligomers were systematically studied using density functional theory and traditional Marcus theory in term of geometric structures, frontier molecular orbitals, ionization potentials (IP), electron affinities (EA), reorganization energies, charge transfer integrals, crystal packing models, and charge transfer mobilities. The IP/EA decreased/increased with increasing oligomer length in PBTzIn , rendering long PBTzIn oligomers showing both p- and n-type characteristic of organic semiconductors. The orbital energy level and mobility show saturation characteristics for n = 6. PBTzI8 shows high and balanced hole/electron mobility of 1.089/0.249 cm2 V−1s−1 and thus is good ambipolar semiconductor. The introduced three thiophene rings in PBTzI3Tm (m = 1–4) enhances the backbone conjugate property and reduces the hole injection barrier. Substituting thiophene H atoms with F further enhances the interaction between the non-covalent bond N...S and S...F and thus increases the molecular planarity, rendering PBTzI3T-2Fm (m = 1–4) being better semiconductor. PBTzI3T3 is ambipolar organic semiconductor with hole/electron mobility of 11.760/1.396 cm2V−1s−1, while PBTzI3T-2F3 and PBTzI3T-2F4 show better ambipolar organic semiconductor performance with much larger hole/electron mobility of 16.325/3.674 cm2V−1s−1 and 60.019/5.086 cm2V−1s−1. • Three series of oligomers containing functionalized imide and thiophen rings were designed. • Roles of oligomer length, thiophen donor, and fluorine-substitution on the charge transfer properties were clarified. • Geometric structures, frontier molecular orbitals, ionizationpotentials (IP), electron affinities (EA) were studied. • Reorganization energies, charge transfer integrals, crystal packing models, and charge transfer mobilities were predicted. • New types of n- and ambipolar semiconductors with very high mobilities were designed. [ABSTRACT FROM AUTHOR]

• Different electronic donating/accepting groups (Na, MP, MB, BN) were introduced onto the C8 position of 5-phenyl-5H-benzo[ b ]phosphindole 5-oxide(PhBPO). • Substitution effect on the structure and spectral properties was revealed according to density functional theory (DFT) calculation. • ground state geometries, orbital energy gaps, infrared (IR) spectra, UV–vis spectra, and fluorescence spectra of these PhBPO derivatives were described systematically. • These compounds possess easy-to-modify sites and are good candidates as potential functional building block. • These compounds are good fluorescence materials and substitution helps increase the fluorescence strength. The properties of phosphole-based π-conjugated compounds could be well tuned via simple chemical modification. Four π-conjugated groups with different electronic nature including naphthalen-2-yl, 4-methoxyphenyl, 4-Methyl benzoate, and 4-benzonitrile were introduced to the C8 position of 5-phenylbenzo[ b ]phosphindole 5-oxide (PhBPO) to reveal the relationship between structures and properties. Density functional theory (DFT) calculations were carried out to comparatively study the ground state geometries, orbital energy gaps, infrared (IR) spectra, UV–vis spectra, and fluorescence (FL) spectra of the five PhBPO derivatives. Good correspondences between the simulated and experimental IR and UV–vis spectral properties were found, proving the feasibility of the DFT method. The IR and Uv-vis spectra were assigned and explained in detail on the basis of the calculation results and the substituional effect of different substituents on the structure and spectral properties was revealed. The large FL oscillator strengths indicate these PhBPO derivatives are good candidates for fluorescent materials. PhBPO derivatives possess easy-to-modify sites and thus can be further utilized as functional materials. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• 24 donor−acceptor dithienyl-diketopyrrolopyrrole-based oligomers were studied. • effects of oligomer length, different Ar groups, and different Ar position on the structures and charge transfer properties were revealed. • single-crystal structure of DPP derivatives was predicted theoretically. • Reorganization energies, charge transfer integrals, charge carrier mobilities were systematically studied. • Semiconductor nature and performance could be tuned upon molecule design. Diketopyrrolopyrrole (DPP)-containing polymers are among the highest mobility semiconductors for field-effect transistor applications. The molecular geometries, electronic structures and charge transport properties as ambipolar organic semiconductors of two series of total 24 donor–acceptor dithienyl-diketopyrrolopyrrole-based oligomers mDTDPPAr and nBDTDPPAr (m = 1–4, n = 1–2, Ar = TT, BT, BDT, TVT) are investigated theoretically through density functional theory and classical Marcus charge transfer theory. The effects of oligomer length form = 1–4, different Ar groups, and different Ar position on the structures and charge transfer properties are systematically studied. It was found that expanding π-conjugate backbone is a viable method to improve their semiconductor performance. Oligomers 4DTDPPTT, 4DTDPPBT, 4DTDPPTVT possess prominent ambipolar semiconductors properties with charge transfer mobilities of 9.62, 10.73, 12.60 cm2 V−1 s−1 for hole and of 7.54, 8.06, 15.56 cm2 V−1 s−1 for electron, respectively. 4DTDPPBDT exhibits large but unbalanced ambipolar performance with hole/electron transfer mobilities of 10.86/20.17 cm2 V−1 s−1 due to the special conjugation of BDT. Changing the order and position of donor and acceptor units has less significant influence on charge transfer mobility. Anisotropic mobilities are also studied to clarify the different charge transfer directions. [ABSTRACT FROM AUTHOR]