نتایج جستجو برای: Transition metal clusters

تعداد نتایج: 542856  

Journal: :Physical chemistry chemical physics : PCCP 2008
Dmitry Yu Zubarev Boris B Averkiev Hua-Jin Zhai Lai-Sheng Wang Alexander I Boldyrev

Aromaticity is an important concept in chemistry primarily for organic compounds, but it has been extended to compounds containing transition-metal atoms. Recent findings of aromaticity and antiaromaticity in all-metal clusters have stimulated further research in describing the chemical bonding, structures and stability in transition-metal clusters and compounds on the basis of aromaticity and ...

Journal: :The journal of physical chemistry. A 2007
Matthew A Addicoat Mark A Buntine Gregory F Metha Andrew T B Gilbert Peter M W Gill

Ionization potentials (IPs) or electron affinities (EAs) for transition metal clusters are an important property that can be used to identify and differentiate between clusters. Accurate calculation of these values is therefore vital. Previous attempts using a variety of DFT models have correctly predicted trends, but have relied on the use of scaling factors to compare to experimental IPs. In ...

Journal: :Solid State Communications 2001

پایان نامه :وزارت علوم، تحقیقات و فناوری - پژوهشگاه پلیمر و پتروشیمی ایران - پژوهشکده علوم و تکنولوژی پلیمر 1391

پلیمریزاسیون اتیلن مدت های مدیدی است که از روش های مختلف انجام شده است این روش ها از پلیمریزاسیون رادیکالی در دما وفشار بالا آغاز شد و به مرور زمان حجم تولیدآن با استفاده از سیستم های کاتالیستی به شدت افزایش یافت. پلیمریزاسیون های کاتالیستی نسبت به روش های سابق پلیمریزاسیون مزایای بسیار زیادی دربرداشت که از جمله می توان به پایین آمدن دما وفشار واکنش تا حد بسیار قابل توجه اشاره کرد. اما یکی از ا...

Journal: :Rapid communications in mass spectrometry : RCM 2003
Xia Zhang Zichao Tang Zhen Gao

By using laser ablation of the mixtures of a transition metal (M: Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pd, Ag) plus lead, M/Pb binary cluster anions were observed except for Zn, and the number of transition metal atoms contained in the binary clusters is at most 4. This behavior is different from that reported previously for M/Ge binary clusters. The experiments indicate that it is also very difficu...

Journal: :Physical review letters 2007
Ewald Janssens Philipp Gruene Gerard Meijer Ludger Wöste Peter Lievens André Fielicke

We report on an element-dependent critical size for argon physisorption at 80 K on transition-metal-doped silicon clusters. Argon does not attach to elemental silicon clusters but only to surface-located transition-metal atoms. Thus physisorption provides structural information. Specifically, the minimal cluster size for the formation of endohedral singly metal-doped silicon cages has been dete...

Journal: :Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 2010
Sandra Scharfe Thomas F Fässler

Homoatomic polyanions have the basic capability for a bottom-up synthesis of nanostructured materials. Therefore, the chemistry and the structures of polyhedral nine-atom clusters of tetrel elements [E(9)](4-) is highlighted. The nine-atom Zintl ions are available in good quantities for E = Si-Pb as binary alkali metal (A) phases of the composition A(4)E(9) or A(12)E(17). Dissolution or extract...

Journal: :The Journal of Chemical Physics 2010

Journal: :Journal of Non-Crystalline Solids 1996

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید