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1.
akir Aydoan Mustafa Salam Abdulmecit Türüt 《Journal of Polymer Science.Polymer Physics》2006,44(11):1572-1579
The polypyrrole/p‐InP structure has been fabricated by the electrochemical polymerization of the organic polypyrrole onto the p‐InP substrate. The current–voltage (I–V), capacitance–voltage (C–V), and capacitance–frequency (C–f) characteristics of the PPy/p‐InP structure have been determined at room temperature. The structure showed nonideal I–V behavior with the ideality factor and the barrier height 1.48 and 0.69 eV respectively. C–f measurements of the structure have been carried out using the Schottky capacitance spectroscopy technique and it has been seen that there is a good agreement between the experimental and theoretical values. Also, it has been seen that capacitance almost show a plateau up to a certain value of frequency, after which, the capacitance decreases. The higher values of capacitance at low frequencies were attributed to the excess capacitance resulting from the interface states in equilibrium with the p‐InP that can follow the a.c. signal. The interface state density Nss and relaxation time τ of the structure were determined from C–f characteristics. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1572–1579, 2006 相似文献
2.
Controlling the electrical characteristics of Au/n‐Si structure with and without (biphenyl‐CoPc) and (OHSubs‐ZnPc) interfacial layers at room temperature
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Nalan Baraz İbrahim Yücedağ Ahmet Demir Gülçin Ersöz Şemsettin Altındal Mehmet Kandaz 《先进技术聚合物》2017,28(8):952-957
In order to interpret well whether or not the organic or polymer interfacial layer is effective on performance of the conventional Au/n‐Si (metal semiconductor [MS]) type Schottky barrier diodes (SBDs), in respect to ideality factor (n ), leakage current, rectifying rate (RR ), series and shunt resistances (Rs , Rsh ) and surface states (Nss ) at room temperature, both Au/biphenyl‐CoPc/n‐Si (MPS1) and Au/OHSubs‐ZnPc/n‐Si (MPS2) type SBDs were fabricated. The electrical characteristics of these devices have been investigated and compared by using forward and reverse bias current–voltage (I–V ) characteristics in the voltage range of (?4 V)–(4 V) for with and without (biphenyl‐CoPc) and (OHSubs‐ZnPc) interfacial layers at room temperature. The main electrical parameters of these diodes such as reverse saturation current (I0 ), ideality factor (n ), zero‐bias barrier height (ΦB0 ), RR , Rs and Rsh were found as 1.14 × 10?5 A, 5.8, 0.6 eV, 362, 44 Ω and 15.9 kΩ for reference sample (MS), 7.05 × 10?10 A, 3.8, 0.84 eV, 2360, 115 Ω and 270 kΩ for MPS1 and 2.16 × 10?7 A, 4.8, 0.7 eV, 3903, 62 Ω and 242 kΩ for MPS2, respectively. It is clear that all of these parameters considerably change by using an organic interfacial layer. The energy density distribution profile of Nss was found for each sample by taking into account the voltage dependence of effective barrier height (Φe ) and ideality factor, and they were compared. Experimental results confirmed that the use of biphenyl‐CoPc and OHSubs‐ZnPc interfacial layer has led to an important increase in the performance of the conventional of MS type SBD. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
3.
Habibe Uslu Mert Y?ld?r?m?emsettin Alt?ndal Perihan Durmu? 《Radiation Physics and Chemistry》2012,81(4):362-369
The effect of 60Co (γ-ray) irradiation on the electrical and dielectric properties of Au/Polyvinyl Alcohol (Ni,Zn-doped)/n-Si Schottky barrier diodes (SBDs) has been investigated by using capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements at room temperature and 1 MHz. The real capacitance and conductance values were obtained by eliminating series resistance (Rs) effect in the measured capacitance (Cm) and conductance (Gm) values through correction. The experimental values of the dielectric constant (ε′), dielectric loss (ε″), loss tangent (tanδ), ac electrical conductivity (σac) and the real (M′) and imaginary (M″) parts of the electrical modulus were found to be strong functions of radiation and applied bias voltage, especially in the depletion and accumulation regions. In addition, the density distribution of interface states (Nss) profile was obtained using the high-low frequency capacitance (CHF-CLF) method for before and after irradiation. The Nss-V plots give two distinct peaks for both cases, namely before radiation and after radiation, and those peaks correspond to two different localized interface states regions at M/S interface. The changes in the dielectric properties in the depletion and accumulation regions stem especially from the restructuring and reordering of the charges at interface states and surface polarization whereas those in the accumulation region are caused by series resistance effect. 相似文献
4.
Dr. Luca Rocchigiani Prof. Vincenzo Busico Dr. Antonello Pastore Prof. Dr. Giovanni Talarico Prof. Dr. Alceo Macchioni 《Angewandte Chemie (International ed. in English)》2014,53(8):2157-2161
NMR spectroscopy and DFT studies indicate that the Symyx/Dow Hf(IV)–pyridylamido catalytic system for olefin polymerization, [{N?,N,CNph?}HfMe][B(C6F5)4] ( 1 , Nph=naphthyl), interacts with ERn (E=Al or Zn, R=alkyl group) to afford unusual heterobimetallic adducts [{N?,N}HfMe(μ‐CNph)(μ‐R)ERn?1][B(C6F5)4] in which the cyclometalated Nph acts as a bridge between Hf and E. 1H VT (variable‐temperature) EXSY NMR spectroscopy provides direct evidence of reversible alkyl exchanges in heterobimetallic adducts, with ZnR2 showing a higher tendency to participate in this exchange than AlR3. 1‐Hexene/ERn competitive reactions with 1 at 240 K reveal that the formation of adducts is strongly favored over 1‐hexene polymerization. Nevertheless, a slight increase in the temperature (to >265 K) initiates 1‐hexene polymerization. 相似文献
5.
Martin Quick Marc‐André Kasper Celin Richter Dr. Rainer Mahrwald Dr. Alexander L. Dobryakov Dr. Sergey A. Kovalenko Dr. Nikolaus P. Ernsting 《Chemphyschem》2015,16(18):3824-3835
β‐Carotene in n‐hexane was examined by femtosecond transient absorption and stimulated Raman spectroscopy. Electronic change is separated from vibrational relaxation with the help of band integrals. Overlaid on the decay of S1 excited‐state absorption, a picosecond process is found that is absent when the C9‐methyl group is replaced by ethyl or isopropyl. It is attributed to reorganization on the S1 potential energy surface, involving dihedral angles between C6 and C9. In Raman studies, electronic states S2 or S1 were selected through resonance conditions. We observe a broad vibrational band at 1770 cm?1 in S2 already. With 200 fs it decays and transforms into the well‐known S1 Raman line for an asymmetric C=C stretching mode. Low‐frequency activity (<800 cm?1) in S2 and S1 is also seen. A dependence of solvent lines on solute dynamics implies intermolecular coupling between β‐carotene and nearby n‐hexane molecules. 相似文献
6.
ESR Studies on the Micellization Behaviors of a Series of Novel Asymmetric Gemini Surfactants 总被引:2,自引:0,他引:2
IntroductionInrecentyears ,bis(quaternaryammonium)surfac tantsorgeminisurfactants ,inwhichtwocationicsurfac tantmoietiesareconnectedwiththeammoniumheadgroupbyaploymethylenechain ,namely ,aspacerhavebecomeofinterestduetotheirexceptionalsurfaceactivityandrem… 相似文献
7.
Intramolecular H?Ar Ligand Exchange between Silicon and Boron: Functionality Transfer of Si?H to B?H
Prof. Dr. Atsushi Kawachi Hiroshi Morisaki Norimasa Nishioka Prof. Dr. Yohsuke Yamamoto 《化学:亚洲杂志》2012,7(3):546-553
o‐C6H4(SiR3?nHn)(BMes2) ( 1 ; R=Me, Ph; n=1, 2) undergo Mes? H (Mes=mesityl) ligand exchange between the silicon atom and the boron atom to form o‐C6H4(SiMesR3?nHn?1)(BMesH) ( 6 ) upon heating. The resulting hydroborane intermediates ( 6 ) immediately react with benzaldehyde to afford their corresponding benzyloxyboranes ( 5 ). A DFT study of model compounds reveals the transition states of the ligand exchange. A hydride abstraction from the silicon atom by the boron center is key to reaching the transition states, which include the tricoordinate silyl‐cation moiety and the tetracoordinate hydridoborate moiety. 相似文献
8.
SN1‐SN2 and SN2‐SN3 mechanistic changes revealed by transition states of the hydrolyses of benzyl chlorides and benzenesulfonyl chlorides
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Shinichi Yamabe Guixiang Zeng Wei Guan Shigeyoshi Sakaki 《Journal of computational chemistry》2014,35(15):1140-1148
Hydrolysis reactions of benzyl chlorides and benzenesulfonyl chlorides were theoretically investigated with the density functional theory method, where the water molecules are explicitly considered. For the hydrolysis of benzyl chlorides (para‐Z? C6H4? CH2? Cl), the number of water molecules (n) slightly influences the transition‐state (TS) structure. However, the para‐substituent (Z) of the phenyl group significantly changes the reaction process from the stepwise (SN1) to the concerted (SN2) pathway when it changes from the typical electron‐donating group (EDG) to the typical electron‐withdrawing one (EWG). The EDG stabilizes the carbocation (MeO? C6H4? CH2+), which in turn makes the SN1 mechanism more favorable and vice versa. For the hydrolysis of benzenesulfonyl chlorides (para‐Z? C6H4? SO2? Cl), both the Z group and n influence the TS structure. For the combination of the large n value (n > 9) and EDG, the SN2 mechanism was preferred. Conversely, for the combination of the small n value and EWG, the SN3 one was more favorable. © 2014 Wiley Periodicals, Inc. 相似文献
9.
《Radiation Physics and Chemistry》2008,77(1):74-78
The effect of 60Co (γ-ray) irradiation on the electrical properties of Au/SnO2/n-Si (MIS) structures has been investigated using the capacitance–voltage (C–V) and conductance–voltage (G/ω−V) measurements in the frequency range 1 kHz to 1 MHz at room temperature. The MIS structures were exposed to γ-rays at a dose rate of 2.12 kGy/h in water and the range of total dose was 0–500 kGy. It was found that the C–V and G/ω−V curves were strongly influenced with both frequency and the presence of the dominant radiation-induced defects, and the series resistance was increased with increasing dose. Also, the radiation-induced threshold voltage shift (ΔVT) strongly depended on radiation dose and frequency, and the density of interface states Nss by Hill–Coleman method decreases with increasing radiation dose. 相似文献
10.
A new oxovanadium(V) complex with the mixed ligand of 2-oxopropionic acid benzoylhydrazone (C10H10N2O3) and benzoylhydrazine (C7H8N2O), VO(C7H7N2O)(C10H9N2O3), has been synthesized. Its structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to monoclinic system with space group P21/n and cell parameters: a=1.1136(4) nm, b=0.6217(2) nm, c=2.6038(9) nm, β=97.182(6)°, V= 1.7887(11) nm^3, Z=4, F(000)=836, Mr=407.28, Dc= 1.512 g/cm^3,μ (Mo Kα) =0.592 mm^-1, R1 =0.0445, wR2= 0.1203. Vanadium atom is 6-coordinated by carboxyl and carbonyl O atoms and N atom of one tridentate C10H10N2O3 to form two stable five-membered rings with the same edge, and the other coordinated atoms of N and O come from one bidentate benzoylhydrazine C7H8N2O. The title complex has a six-coordinated V center [VO(N2O3)] with a distorted octahedral arrangement. In the crystal lattice, there are hydrogen bonding interactions between two molecules. 相似文献
11.
Ramn Macías Simon A. Barrett Jonathan Bould Udo Drfler Josef Holub John D. Kennedy Mark Thornton‐Pett Bohumil tíbr 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):520-522
Neutral 8‐(5‐iodo‐n‐pentyl)‐3‐(η5‐pentamethylcyclopentadienyl)‐arachno‐3‐rhoda‐7,8‐dithiaundecaborane, [Rh(C5H19B8IS2)(C10H15)], obtained from the [arachno‐7,8‐S2B9H10]? anion by treatment with I(CH2)5I followed by [Rh(C5Me5)Cl2]2 and N,N,N′,N′‐tetramethyl‐1,8‐diaminonaphthalene, has the 11‐vertex cluster geometry of [arachno‐7,8‐S2B9H10]?, but with an {Rh(C5Me5)} unit in the 3‐position instead of a {BH} unit, and with a –(CH2)5I chain attached exo to an S atom. 相似文献
12.
Coupling of Bifunctional CoMn‐Layered Double Hydroxide@Graphitic C3N4 Nanohybrids towards Efficient Photoelectrochemical Overall Water Splitting
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Muhammad Arif Ghulam Yasin Muhammad Shakeel Xiaoyu Fang Rui Gao Prof. Shengfu Ji Prof. Dongpeng Yan 《化学:亚洲杂志》2018,13(8):1045-1052
The development of durable, low‐cost, and efficient photo‐/electrolysis for the oxygen and hydrogen evolution reactions (OER and HER) is important to fulfill increasing energy requirements. Herein, highly efficient and active photo‐/electrochemical catalysts, that is, CoMn‐LDH@g‐C3N4 hybrids, have been synthesized successfully through a facile in situ co‐precipitation method at room temperature. The CoMn‐LDH@g‐C3N4 composite exhibits an obvious OER electrocatalytic performance with a current density of 40 mA cm?2 at an overpotential of 350 mV for water oxidation, which is 2.5 times higher than pure CoMn‐LDH nanosheets. For HER, CoMn‐LDH@g‐C3N4 (η50=?448 mV) requires a potential close to Pt/C (η50=?416 mV) to reach a current density of 50 mA cm2. Furthermore, under visible‐light irradiation, the photocurrent density of the CoMn‐LDH@g‐C3N4 composite is 0.227 mA cm?2, which is 2.1 and 3.8 time higher than pristine CoMn‐LDH (0.108 mA cm?2) and g‐C3N4 (0.061 mA cm?2), respectively. The CoMn‐LDH@g‐C3N4 composite delivers a current density of 10 mA cm?2 at 1.56 V and 100 mA cm?2 at 1.82 V for the overall water‐splitting reaction. Therefore, this work establishes the first example of pure CoMn‐LDH and CoMn‐LDH@g‐C3N4 hybrids as electrochemical and photoelectrochemical water‐splitting systems for both OER and HER, which may open a pathway to develop and explore other LDH and g‐C3N4 nanosheets as efficient catalysts for renewable energy applications. 相似文献
13.
《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(13):3154-3161
IR photodissociation spectra of mass‐selected clusters composed of protonated benzene (C6H7+) and several ligands L are analyzed in the range of the C? H stretch fundamentals. The investigated systems include C6H7+? Ar, C6H7+? (N2)n (n=1–4), C6H7+? (CH4)n (n=1–4), and C6H7+? H2O. The complexes are produced in a supersonic plasma expansion using chemical ionization. The IR spectra display absorptions near 2800 and 3100 cm?1, which are attributed to the aliphatic and aromatic C? H stretch vibrations, respectively, of the benzenium ion, that is, the σ complex of C6H7+. The C6H7+? (CH4)n clusters show additional C? H stretch bands of the CH4 ligands. Both the frequencies and the relative intensities of the C6H7+ absorptions are nearly independent of the choice and number of ligands, suggesting that the benzenium ion in the detected C6H7+? Ln clusters is only weakly perturbed by the microsolvation process. Analysis of photofragmentation branching ratios yield estimated ligand binding energies of the order of 800 and 950 cm?1 (≈9.5 and 11.5 kJ mol?1) for N2 and CH4, respectively. The interpretation of the experimental data is supported by ab initio calculations for C6H7+? Ar and C6H7+? N2 at the MP 2/6‐311 G(2df,2pd) level. Both the calculations and the spectra are consistent with weak intermolecular π bonds of Ar and N2 to the C6H7+ ring. The astrophysical implications of the deduced IR spectrum of C6H7+ are briefly discussed. 相似文献
14.
CPMD/GULP QM/MM interface for modeling periodic solids: Implementation and its application in the study of Y‐zeolite supported Rhn clusters
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We report here the development of hybrid quantum mechanics/molecular mechanics (QM/MM) interface between the plane‐wave density functional theory based CPMD code and the empirical force‐field based GULP code for modeling periodic solids and surfaces. The hybrid QM/MM interface is based on the electrostatic coupling between QM and MM regions. The interface is designed for carrying out full relaxation of all the QM and MM atoms during geometry optimizations and molecular dynamics simulations, including the boundary atoms. Both Born–Oppenheimer and Car–Parrinello molecular dynamics schemes are enabled for the QM part during the QM/MM calculations. This interface has the advantage of parallelization of both the programs such that the QM and MM force evaluations can be carried out in parallel to model large systems. The interface program is first validated for total energy conservation and parallel scaling performance is benchmarked. Oxygen vacancy in α‐cristobalite is then studied in detail and the results are compared with a fully QM calculation and experimental data. Subsequently, we use our implementation to investigate the structure of rhodium cluster (Rhn; n = 2 to 6) formed from Rh(C2H4)2 complex adsorbed within a cavity of Y‐zeolite in a reducible atmosphere of H2 gas. © 2016 Wiley Periodicals, Inc. 相似文献
15.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):400-405
The search for new tuberculostatics is an important issue due to the increasing resistance of Mycobacterium tuberculosis to existing agents and the resulting spread of the pathogen. Heteroaryldithiocarbazic acid derivatives have shown potential tuberculostatic activity and investigations of the structural aspects of these compounds are thus of interest. Three new examples have been synthesized. The structure of methyl 2‐[amino(pyridin‐3‐yl)methylidene]hydrazinecarbodithioate, C8H10N4S2, at 293 K has monoclinic (P21/n) symmetry. It is of interest with respect to antibacterial properties. The structure displays N—H…N and N—H…S hydrogen bonding. The structure of N′‐(pyrrolidine‐1‐carbonothioyl)picolinohydrazonamide, C11H15N5S, at 100 K has monoclinic (P21/n) symmetry and is also of interest with respect to antibacterial properties. The structure displays N—H…S hydrogen bonding. The structure of (Z)‐methyl 2‐[amino(pyridin‐2‐yl)methylidene]‐1‐methylhydrazinecarbodithioate, C9H13N4S2, has triclinic (P) symmetry. The structure displays N—H…S hydrogen bonding. 相似文献
16.
Dr. Yongguang Li Dr. Le Zhao Dr. Anthony Yiu‐Yan Tam Dr. Keith Man‐Chung Wong Prof. Dr. Lixin Wu Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(43):14496-14505
A new series of platinum(II) complexes with tridentate ligands 2,6‐bis(1‐alkyl‐1,2,3‐triazol‐4‐yl)pyridine and 2,6‐bis(1‐aryl‐1,2,3‐triazol‐4‐yl)pyridine (N7R), [Pt(N7R)Cl]X ( 1 – 7 ) and [Pt(N7R)(C?CR′)]X ( 8 – 17 ; R=n‐C4H9, n‐C8H17, n‐C12H25, n‐C14H29, n‐C18H37, C6H5, and CH2‐C6H5; R′=C6H5, C6H4‐CH3‐p, C6H4‐CF3‐p, C6H4‐N(CH3)2‐p, and cholesteryl 2‐propyn‐1‐yl carbonate; X=OTf?, PF6?, and Cl?), has been synthesized and characterized. Their electrochemical and photophysical properties have also been studied. Two amphiphilic platinum(II)? 2,6‐bis(1‐dodecyl‐1,2,3‐triazol‐4‐yl)pyridine complexes ( 3‐Cl and 8 ) were found to form stable and reproducible Langmuir–Blodgett (LB) films at the air/water interface. These LB films were characterized by the study of their surface‐pressure–molecular‐area (π–A) isotherms, XRD, and IR and polarized‐IR spectroscopy. 相似文献
17.
In this study, the forward bias current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the Al/TiO2/p-Si (MIS) structures derived using the sol–gel method have been investigated and compared at various preparation temperatures.
Experimental results show that the preparation temperatures strongly affect the electrical characteristics, such as ideality
factor (n), zero-bias barrier height (), series resistance (R
s
) and interface states (N
ss
). The MIS structures show non-ideal behavior of I–V characteristics with an n varying between 2.17 and 4.61. We have found that the and R
s
increase as the n decrease with increasing preparation temperature. The energy distribution profile of N
ss
of the Al/TiO2/p-Si (MIS) structures was obtained from the forward bias I–V characteristics by taking into account both the bias dependence of the effective barrier height () and R
s
for various preparation temperatures. The values of N
ss
increase from the midgap towards the top of valance band for various preparation temperatures. 相似文献
18.
Hongya Li Biao Yan Haixia Ma Zhiyong Sun Yajun Ma Zhifang Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(1):64-68
Bis(5‐amino‐1,2,4‐triazol‐3‐yl)methane (BATZM, C5H8N8) was synthesized and its crystal structure characterized by single‐crystal X‐ray diffraction; it belongs to the space group Fdd2 (orthorhombic) with Z = 8. The structure of BATZM can be described as a V‐shaped molecule with reasonable chemical geometry and no disorder. The specific molar heat capacity (Cp,m) of BATZM was determined using the continuous Cp mode of a microcalorimeter and theoretical calculations, and the Cp,m value is 211.19 J K?1 mol?1 at 298.15 K. The relative deviations between the theoretical and experimental values of Cp,m, HT – H298.15K and ST – S298.15K of BATZM are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM were estimated using the nitrogen equivalent equation according to the experimental density; BATZM has a higher detonation velocity (7954.87 ± 3.29 m s?1) and detonation pressure (25.72 ± 0.03 GPa) than TNT. 相似文献
19.
Ying Huang Bo Chen Jian Duan Fei Yang Tengrui Wang Zhengfeng Wang Wenjuan Yang Chenchen Hu Wei Luo Yunhui Huang 《Angewandte Chemie (International ed. in English)》2020,59(9):3699-3704
Solid‐state Li metal batteries (SSLMBs) have attracted considerable interests due to their promising energy density as well as high safety. However, the realization of a well‐matched Li metal/solid‐state electrolyte (SSE) interface remains challenging. Herein, we report g‐C3N4 as a new interface enabler. We discover that introducing g‐C3N4 into Li metal can not only convert the Li metal/garnet‐type SSE interface from point contact to intimate contact but also greatly enhance the capability to suppress the dendritic Li formation because of the greatly enhanced viscosity, decreased surface tension of molten Li, and the in situ formation of Li3N at the interface. Thus, the resulting Li‐C3N4|SSE|Li‐C3N4 symmetric cell gives a significantly low interfacial resistance of 11 Ω cm2 and a high critical current density (CCD) of 1500 μA cm?2. In contrast, the same symmetric cell configuration with pristine Li metal electrodes has a much larger interfacial resistance (428 Ω cm2) and a much lower CCD (50 μA cm?2). 相似文献
20.
NMR Spectroscopy and X‐Ray Characterisation of Cationic N‐Heteroaryl‐Pyridylamido ZrIV Complexes: A Further Level of Complexity for the Elusive Active Species of Pyridylamido Olefin Polymerisation Catalysts
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Dr. Gang Li Dr. Cristiano Zuccaccia Dr. Consiglia Tedesco Dr. Ilaria D'Auria Prof. Dr. Alceo Macchioni Prof. Dr. Claudio Pellecchia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(1):232-244
New [(N?,N,N?)ZrR2] dialkyl complexes (N?,N,N?=pyrrolyl‐pyridyl‐amido or indolyl‐pyridyl‐amido; R=Me or CH2Ph) have been synthesised and tested as pre‐catalysts for ethene and propene polymerisation in combination with different activators, such as B(C6F5)3, [Ph3C][B(C6F5)4], [HNMe2Ph][B(C6F5)4] or solid AlMe3‐depleted methylaluminoxane (DMAO). Polyethylene (Mw>2 MDa and Mw/Mn = 1.3–1.6) has been produced if pre‐catalysts were activated with 1000 equivalents of DMAO (based on Al) [activity >1000 kgPE (mol[Zr] h mol atm)?1] or by using a higher pre‐catalyst concentration and a mixture of [HNPhMe2][B(C6F5)4] (1 equiv) and AliBu2H (60 equiv). In the case of propene polymerisation, activity has been observed only if pre‐catalysts were treated with an excess of AliBu2H prior to addition of DMAO, which led to highly isotactic polypropylene ([mmmm]>95 %). Neutral pre‐catalysts and ion pairs derived from their activation have been characterised in solution by using advanced 1D and 2D NMR spectroscopy experiments. The detection and rationalisation of intercationic NOEs clearly showed the formation of dimeric species in which some pyrrolyl or indolyl π‐electron density of one unit is engaged in stabilising the metal centre of the other unit, which relegates the counterions in the second coordination sphere. The solid‐state structure of the dimeric indolyl‐pyridyl‐amidomethylzirconium derivative, determined by X‐ray diffraction studies, points toward a weak Zr???η3‐indolyl interaction. It can be hypothesised that the formation of dimeric cationic species hampers monomer coordination (especially of less reactive α‐olefins) and that addition of AliBu2H is crucial to split the homodimers. 相似文献