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Conclusions 
1. It is shown that the density functional method with use of pseudopotential basis set for mercury 
atom and 6-311+G(d,p)  for other atoms in the software package GAUSSIAN’03 and TZ2P+ program of 
ADF gives adequate results in predicting of the geometrical parameters and IR spectra of mercury 
compounds. 
2. The analysis of the bonding in the structure of the cation and ammonium radical in the framework 
of method of the natural bond orbitals was carried out. It is shown that the most likely of interaction with 
the surface of metallic mercury has an ammonium cation, which is in tetrahedral surrounding with four 
mercury atoms. 
3. The GAUSSIAN’03 and ADF programs calculated the thermodynamic parameters and showed the 
inability to interact with the surface of metallic mercury such amines as hydroxylamine, hydrazine, and 
tetra-methylamine. 
 
REFERENCES 
 
[1]
 
Gmelis Handbuch der Anorganischen chemie. 1936. 23. Ammonium, B. s. 9. Gmelis Handbuch der Anorganischen 
chemie. 1962. P.1006-1050. 
[2]
 
Stromberg A.G., Konkova A.V. Method of determination of ammonium solubility in mercury. Journal of physical 
chemistry. 1968. Т.42.P.2063. 
[3]
 
Syroeshkina T.V., Raimzhanova M.M., Erkasov R.Sh. About thermal decomposition of amalgams of ammonium and 
hydrazonium.Collection of works on chemistry. Alma-Ata: KazSU. 1970. P.7. 

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22  
[4]
 
Ostrovskaya S.E., Cventarnyi E.G., Durdin Ya.V. To charge of ammonium ion on mercury electrod. Electrochemistry
1973. Т.9. P.995. 
[5]
 
Mercalova V.E. Condition of electrolytic obtainment of ammonium amalgam and some its electrochemical properties. 
Applied and theor. chemistry1977. P.119. 
[6]
 
Gladyshev V.P., Zebreva A.I., Syroeshkina T.V., Raimzhanova M.M. Processes of interfacial exchange in the systems 
of ammonium amalgam –solutions of metals salts. Proceedings of HEEs. Chemistry and chemical technology.  1978.  Т.21. 
P.1474. 
[7]
 
Gladyshev V.P., Syroeshkina T.V. Electrochemistry of amalgams of onien radicals. Potentials and mechanism of 
ammonium amalgam decomposition. Electrochemistry1979. Т.40. P.1523. 
[8]
 
C.J. Nyman, J.L. Ragle, P.F. Linde. Polarographic characteristics of ammonium ion and ammonia. Anal. Сhem1960
Vol.32. P.352. 
[9]
 
R.J. Johnston, A.R. Ubbelohde. The formation of ammonium amalgam by electrolysis. J. Chem. Soc.  1951. Vol.7. 
P.1731. 
[10]
 
E.M. Rich, M.W. Travers. The constitution of ammonium amalgam. J. Chem. Soc1907. Vol.29. P.844. 
[11]
 
E. Kariv – Miller, G.K. Lehman, V. Svetlicic. Ammonium – mercury, electrogeneration and properties. J. Elektroanal. 
Chem1997. Vol.423. P.87. 
[12]
 
Kovaleva S.V., Gladyshev V.P. Formation of pseudometals hydrides amalgams at electrolysis with mercury catod. 
Journal of general chemistry1997. Т.67. P.342. 
[13]
 
Gladyshev V.P., Kovaleva S.V., Chramcova N.A. determination of ammonium by method of inversion 
voltamperometry. Journal of analytical chemistry2001. Т.56. P.503. 
[14]
 
M.J. Frisch, G.W. Trucks, H.B. Schlegel, P.M.W. Gill, B.G. Johnson, M.A. Robb, J.R. Cheeseman, T. Keith, G.A. 
Petersson, J.A. Montgomery, K. Raghavachari, M.A. Al-Laham, V. Zakrzewski, J.V. Ortiz, J.B. Foresman, J. Closlowski, B.B. 
Stefanov, A. Nanayakkara, M. Challacombe, C.Y. Peng, P.Y. Ayala, W. Chen, M.W. Wong, J.L. Andress, E.S. Replogle, R. 
Gomperts, R.L. Martin, D.J. Fox, J.S. Binkley, D.J. Defress, J. Baker, J.P. Stewart, Head-Gordon, C. Gonzales, J.A. Pople. 
Gaussian 98, Revision A; Gaussian, Inc: Pittsburg, PA. 1998
[15]
 
M.N. Glukhovtsev, A. Pross, M.P. McGrath, L. Radom. J. Chem. Phys1995. Vol.103. P.1878. 
[16]
 
A.D. Becke. J. Chem. Phys. 1993. Vol.98. P.5648. 
[17]
 
C. Lee, W. Yang, R.G. Parr. Phys. Rew. B1988. Vol.37. P.785. 
[18]
 
L.A. Curtiss, K. Raghavachari, P.C. Redfern, J.A. Pople. J. Chem. Phys1997. Vol.106. P.1063. 
[19]
 
E.D. Glendening, A.E. Reed, J.E. Carpenter and F. Weinhold, NBO Version 3.1. ADF2004.01, SCM, Theoretical 
Chemistry, Vrije Universitiet, Amsterdam, The Netherlands, http://www.scm.com 
[20]
 
G. te Velde, F.M. Bickelhaupt, T. Ziegler. J. Comput. Chem. 2001.Vol.22. P.931. 
[21]
 
J.P. Perdew, K. Burke, M. Ernzerhof. Phys. Rev. Lett. 1996. Vol.77. P.3965. 
[22]
 
E. van Lenthe, A.E. Ehlers, E.J. Baerends. J. Chem. Phys1999. Vol.110. P.8943. 
[23]
 
Bacanov S.S. Structural chemistry. Facts and dependences. М.: Dialogue MSU.  2000. 292 p. 
[24]
 
K. Nakamoto. Infrared and Raman Spectra of Inorganic and Coordination Compounds. 5
th
 Edition. N. Y., John Wiley 
and Sons. 1997. Vol.1. 384p.  
 
ТЫҒЫЗДЫҚ ФУНКЦИОНАЛЫ ТЕОРИЯСЫ НЕГІЗІНДЕ МЕТАЛЛ СЫНАП БЕТІНІҢ  
АММОНИЙ НЕГІЗДЕРІМЕН ӨЗАРА ƏСЕРІН ТАЛДАУ 
 
O.Х. Полещук
1
, С.В. Ковалева
2
, М.Н. Ермаханов
3
, П.А. Саидахметов
3

А.Б. Утелбаева
3
, М.А. Нуруллаев
3
 
 
1
Томск ұлттық зерттеу политехникалық университеті, Томск, Рессей; 
2
Бейорганикалық химия кафедрасы, Томск мемлекеттік педагогикалық университет, Томск, Рессей;
 
3
М.О. Əуезов атындағы Оңтүстік Қазақстан мемлекеттік университеті, Шымкент қ., 
Казахстан Республикасы 
 
Түйін  сөздер:  тығызыдқ  функционалының  теориясы,  жалғанпотенциал,  аммоний  негіздері,  металл  сынап, 
байланыстың табиғи орбитальдары. 
Аннотация.  Амстердам  тығыздық  функционалы  бағдарламасындағы GAUSSIAN 03 жəне TZ2P+ бағдарламалық 
пакетіндегі  сынап  атомына  жəне  басқа  атомдарға  арналған 6-311+G(d,p) жалған  потенциалды  базисті  жиынын 
пайдаланып  тығыздық  функционалы  əдісімен  газдық  фазадағы  кейбір  сынап  құрамдас  молекулаларының  есептеулері 
жүргізілді.  Аммоний  катионы  аммоний  радикалына  салыстырғанда  металл  сынап  бетімен  үлкен  ықтималдықпен 
əсерлесетіндігі көрсетілген. Есептелген термиданимикалық параметрлер гидроксиламин, гидразин жəне тетраметиламин 
сияқты аминдер металл сынап бетімен əсерлесуі мүмкін еместігін көрсетеді.  
Поступила 16.05.2016 г. 

ISSN 2224–5227                                                                                                                               
№ 3. 2016  
 
 
23 
REPORTS OF THE NATIONAL ACADEMY OF SCIENCES  
OF THE REPUBLIC OF KAZAKHSTAN 
ISSN 2224-5227 
Volume 3, Number 307 (2016), 23 – 30 
 
УДК 541.1+530.145 
 
АНАЛИЗ ВЗАИМОДЕЙСТВИЯ ЧЕТЫРЕХАТОМНОГО КЛАСТЕРА 
СЕРЕБРА С ПОВЕРХНОСТЬЮ ДИОКСИДА КРЕМНИЯ МЕТОДАМИ 
ТЕОРИИ ФУНКЦИОНАЛА ПЛОТНОСТИ 
 
O. Х. Полещук
1
, Т. И. Изаак
2
, Г.М. Адырбеков
3
, М.Н. Ермаханов
3

П.А. Саидахметов
3
, Р.Т. Абдраимов
3
 
 
1
Национальный исследовательский Томский политехнический университет, Томск, Россия; 
2
Национально-исследовательский Томский государственный университет; 
3
Южно-Казахстанский государственный университет им. М. Ауезова, Шымкент, РК 
 
Ключевые  слова:  теория  функционала  плотности, DGDZVP, диоксид  кремния,   металлическое 
серебро, натуральные орбитали связи. 
Аннотация.  Проведены  расчеты  некоторых  серебро-  и  кремний  содержащих  молекул  в  газовой  фазе 
методом  функционала  плотности  с  использованием  полноэлектронного  базисного  набора DGDZVP в 
программном пакете GAUSSIAN'03 и TZ2P+ в программе Амстердамский функционал плотности. Показано, 
что диоксид кремния с большой вероятностью может взаимодействовать с кластером серебра. Рассчитанные 
рентгеноэлектронные  уровни  натуральных  орбиталей  связи  указывают  на  существенное  взаимодействие 
между разрыхляющими орбиталями атомов серебра. 
 
UDС 541.1+530.145 
 
ANALYSIS OF THE INTERACTION OF FOUR-ATOM SILVER  
CLUSTER WITH SURFACE OF SILICON DIOXIDE  
BY DENSITY FUNCTIONAL THEORY METHODS 
 
O.Kh. Poleshchuk, T.I. Izaak, G.M. Adyrbekova, Ermakhanov, 
P.A. Saidakhmetov, R.T. Abdraimov 
 
1
National Research Tomsk Polytechnic University, Tomsk, Russia; 
2
National Research Tomsk State University, Tomsk, Russia; 
3
M.Auezov South Kazakhstan state University, Shymkent, Kazakhstan 
poleshch@tspu.edu.ru, taina_i@mail.ru, adyrbekova.gulmira@mail.ru, myrza1964@mail.ru,  
timpf_ukgu@mail.ru, raha_ukgu@mail.ru 
 
Keywords: Density Functional Theory, ADF, silicon dioxide, metallic silver, natural orbital bond. 
Abstract. The calculations of some silver- and silicon -containing molecules in the gas phase at the density 
functional method with using all-electron DGDZVP basis set in GAUSSIAN'03 software package and TZ2P+ basis 
set in Amsterdam density functional. It is shown that the silicon dioxide with a high probability can interact with the 
silver cluster. The calculated ESCA levels and natural orbital bond point to a significant interaction between the 
antibonding orbital of silver atoms. 
 
Introduction.  Composite materials consisting of silicon dioxide and deposited on its surface 
particles, clusters and ions of silver are actively researched for use as catalysts in CO afterburning 
effectively employed in low-temperature region and selective with respect to CO and hydrogen [1]. 
At present, it is known that the activity of these catalysts determined by the size of the silver particles 
[2] and the surface composition of the support [3] and the presence of redox-rehabilitation treatments [4]. 

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24  
Previously it has been suggested [5], that in the process of the latter, along with the silver particle 
redispersion [6], the interface layer is formed, which plays a role in the formation of active centers. So the 
study of the interaction of oxidized and reduced silver particles with a silicon dioxide surface defect quite 
true. 
One of the most sensitive methods in this area is the X-ray photoelectron spectroscopy, and the fact 
of the presence of the interface layer was found with its help [5]. 
However, the small magnitude of the contribution of this layer to the overall signal generated by the 
photo-electron beam does not mainly from silver coated surface of the carrier and the array of silver 
particles on the surface does not permit reliable conclusions on its composition and electronic state of 
silver. Earlier calculations have been carried out for uncharged particles and silver clusters Ag
n
 (n = 1-4), 
interacting c unbridged oxygen penny-set (≡Si-O·, NBO-defects), as well as dangling bonds 
≡Si·dehydroxylated surface of SiO
2

In [7, 8] was concluded that the interaction of silver with clusters ≡Si· there is a charge transfer in the 
cluster with the silicon atom, and a defect NBO - clusters on the oxide support. The energies of adsorption 
of silver clusters on the defects of silicon dioxide are calculated. 
It was shown that surface defects can act as a trap of adsorbed silver atoms, diffusion preventing their 
surface, which is important for the interface layer, the nucleation of silver particles and possibly 
functioning of active centers. 
In addition, in [9] it was calculated the interaction of copper clusters, which properties are quite close 
to the properties of silver, with a regular surface of silica and neutral oxygen vacancies (≡Si-Si≡). It is 
shown that the active surface is not regular in relation to the copper clusters, and the activity decreases in 
the number of defects NBO> ≡Si > ≡Si-Si≡. 
In [10] it is shown that the interaction of copper clusters with NBO-defect a significant shift due 2p-
energy level of silicon about 0.6-1 eV is observed only at a small cluster size. For large copper clusters 
shift does not exceed 0.1 eV. 
In [11] it was performed quantum chemical calculations of silver clusters models on hydroxylated 
silica surface in the oxidized and reduced forms and electronic spectra. In this case the calculated and 
experimental spectra containing silver in an oxidized form good matched. However, the calculation of the 
energy of interaction between oxidized forms of silver and surface defects in this work was not carried 
out. 
In [12] it was first noted that the oxygen atoms of the silanol groups of silica involved in the 
formation of the intermediate in the oxidation of CO on platinum particles, and the hydrogen formed 
during the decay of the intermediate with platinum particles and is held constantly returned to the system. 
Quantum-chemical modeling of reversible spillover hydrogen on zeolite-OH groups on the metal 
clusters, rhodium, iridium and gold deposited on the zeolite hydroxylated performed in [13]. 
One way to study the interactions between the silver clusters and the surface of the silicon dioxide 
are theoretical quantum chemical calculations using theory methods density functional (DFT). 
Using a sufficiently accurate functional and basis set allows to receive adequate values of the 
physical parameters required. To investigate the above-mentioned features of these interactions can be 
used cluster models. Small cluster models have shown to be useful in the study of the adsorption of the 
individual components and provide a fairly accurate description of adsorbed structures, vibrations and 
energies of the physical and chemical adsorption [14-17]. 
Using DFT methods, the optimized structure of the four-atomic silver clusters, often used for the 
calculations, is essentially planar and rhombic 
A number of researchers [18-20] have shown that the most optimal in terms of time and computer 
resources, methods to DFT calculations of systems containing atoms of elements of the fifth period 
(including silver), is a combination of three-parameter hybrid functional B3LYP with full-valence-split 
basis with the addition of polarization functions DGDZVP. This basic set of specially optimized for DFT 
calculations of compounds with heavy atoms. 
In this article, we attempt to computer modeling of the interaction between the atomic and cluster 
silver and hydroxylated surface of silica, obtained structural, spectral and energy parameters of the 
complexes.  
Experimental part. Calculations were performed using a standard software package GAUSSIAN 03 
[21]. In order to optimize the geometry of the studied clusters it was used full-DGDZVP basis set, 

ISSN 222
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25 
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№ 3. 2016 
 
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       (2) 

Доклады Национальной академии наук Республики Казахстан  
 
 
   
26  
 
                                                 a)  
 
 
 
 
                 b) 
 
Fig. 2 – The relationship between the calculated and experimental bond lengths in certain compounds  
of silver and silicon in the approximation B3LYP / DGDZVP (a) and BP86TZ2P + (b) 
 
Fig. 2a shows the correlation between the experimental [31] and calculated by B3LYP / DGDZVP 
bond lengths for some silver and silicon compounds: 
 
 
Fig. 3 – The relationship between the experimental and calculated vibrational frequencies in the IR spectrum of some silver 
and silicon compounds at B3LYP DGDZVP 
 
Fig. 3 shows the linear correlation between the calculated at Gaussian program and experimental 
values of the frequencies of the stretching and bending vibrations in the IR spectra of some silver and 
silicon compounds [32] fine quality, which indicates that  calculations correctly describe the vibrational 
transitions. 
 
ω(exp.) = 45.8 + 0.97ω(cal.) r = 0.999; s = 18; n = 13 
       (3) 
 
The good correlations between experimental and calculated bond lengths and vibrational frequencies, 
and the coefficients of R (cal.) close to the unit, indicate a high reliability level used in the calculations. 
The optimized structure of silver nitrides and silicon halides, hydrides, has allowed them to calculate 
the dissociation energy of both the used calculation methods: Gaussian (4) and ADF (5) (Figure 4a, b.). 
 
 
De(exp.) = 113 + 0.55De(cal.)             r = 0.986; s = 26; n = 17 
       (4) 
 
 
De(exp.) = 59 + 0.63De(cal.)               r = 0.986; s = 26; n = 17 
       (5) 
 
The same correlation coefficients and standard deviations of both correlation equations show that the 
two methods of density functional theory can be obtained sufficiently reliable thermodynamic parameters. 
Besides this calculation of electronic absorption spectrum of Ag
4
Si (OH
3
) O
+
 system by 
B3LYP/DGDZVP (291 and 387 nm) and BP86TZ2P+ (298 and 360 nm) methods indicates a good 

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agreement with the experimental spectrum (294, 374-392 nm) [11]. 
Fig. 5 presents the optimized structure of the for-atom clusters of silver complex and silica on both 
levels of the theory. 
It was established that the silver cluster has a tetrahedral structure. The length of the connection 
between adjacent atoms of Ag was 2.774 Å for values tetrahedral bond angles of 60°. 
 
                                        a)                                                                                                    b) 
 
Fig. 4 – The relationship between the experimental and computational B3LYP/ DGDZVP (a) and BP86TZ2P + (b)  
methods of the dissociation energies of some silver and silicon compounds 
 
 
                            
 
                                                           a)                                                                                    b) 
 
Fig. 5 – Optimized structure Ag
4
Si (OH)
3
O+ B3LYP/DGDZVP (a) and BP86TZ2P+ (b) approximation 
 
The resulting optimized bond length Ag-Ag are in agreement with the experimental and calculated 
results (for example, Ag-Ag distance of 2.889 Å [33], 2.838 Å [15], 2.66 Å [16]). 
Some differences in the geometric parameters can be explained by a single positive charge used in 
this paper silver cluster. 
When interacting with the silica surface of the bond lengths Ag-Ag increase somewhat and become 
unequal from 2.86 to 3.01 Å, and the distance from the nearest atom of silver to the coordinated oxygen 
atom is equal to 2.262 and 2.140 Å in different approximation that only a little more of the covalent bond 
length AgO (2.097 Å). 
Changes in bond lengths Ag-Ag reflected in the internal energy levels Ag3d (Table. 1), which 
decreases with the coordination of the calculation of the two methods. This indicates the transfer of the 
electron density to the silver cluster. 
 
 
 

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Table 1 – Calculated  internal energy levels (eV) in the approximations of natural orbitals (nbo),  
Mulliken (Mull) in the Gaussian programs and ADF (adf) 
 
System E
Ag
(nbo) EAg(Mull)  EAg(adf) ESi(nbo) ESi(Mull)  ESi(adf) 
Ag
4

376.2 376.4  365.7   
 
 
Si(OH)
3
O  
 
 
101.4 
101.6 96.2 
Ag
4
Si(OH)
3
O

375.4 375.6  365.5  103.9 104.1  98.5 
 
Comparison between the calculated and experimental level values obtained by ESXA [34] (368 eV) 
leads to good agreement between them (1-3%) for silver clusters. Si2p energy level under the 
coordination increases in all approximations, which indicates the shift of the electron density from the 
silicon atoms in the coordination. 
The redistribution of the electron density on the atoms on the basis of various approximations is 
given in Table. 2. It can be seen that regardless of the approach used in the evaluation of effective charges 
on the atoms, in coordination decreases the electron density on the atoms of silver and silicon. 
 
Table 2 – Change in electron density at one atom in Ag
4
Si(OH)
3
O+, calculated by the B3LYP/DGDZVP (a) and BP86/TZ2P+ (b) 
 
Atom 
∆qMulliken (а) 
∆NBO (а) 
∆qMulliken (б) 
∆qHirsh (б) 
∆qVoronoy (б) 
Ag -0.121 
-0.187 
-0.114 
-0.078 
-0.068 
O(коорд.) 0.422 
0.740 
0.301 
0.172 
0.222 
Si -0.119  -0.075 
-0.005  -0.059 
-0.003 
O 0.082  0.044 
0.065  0.025 
0.026 
The sign (-) corresponds to the decrease in the electron density 
 
In the oxygen atom directly coordinating with silver clusters, the electron density increases 
significantly. Minimal increase in the electron density occurs at the oxygen atoms of the remaining OH 
groups. Apparently serves as a coordinating "bridge" oxygen atom for the transfer of electron density 
from the silver cluster and a central silicon atom to oxygen atoms. 
A similar pattern was observed for the previously non-transition elements complexes with organic 
ligands [35]. From the point of view of the natural orbitals method of chemical bonding connection 
between the cluster of silver and silica is carried out by interaction between the anti-bonding silver lone 
electron pairs between its (Table 3). 
This is also evidenced by the appearance of molecular occupied orbitals (HOMO) and lowest 
unoccupied (LUMO) (Fig. 6). 
 
 
 
 
а) b) c) 
d)  e) 
 
 
 
 
 
 
 
 
Fig. 6. Molecular orbitals of the Ag
4
Si (OH) 
3
O

complex: ВЗМО (a), 
ВЗМО-1 (b), ВЗМО-2 (c), ВЗМО-3 (d), НСМО (e) 
 
The electron density in the HOMO of (a-d) and LUMO (e) belongs to the cluster mainly silver, it 
confirms that such interactions. 
If the cluster Ag
4
+
 silver along with five electron lone pairs of d-type for each atom, there is only one 
pair of electrons anti-bonding s-type, in coordination appear four s-antibonding electron lone pairs of with 
an average population of 0.384e. 
 


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