Semi-empirical molecular orbital theory. The one-centre quantities for the elements of the first and second transition series

Semi-empirical molecular orbital theory. The one-centre quantities for the elements of the first and second transition series

Volume 11, number CHEMICAL PHYSICS LE’ITFXS 3 15 October 197 1 SE~-E~I~~AL.~OLE~~~ ORBITA_L,THEORY. THE ONE~ENT~ Q~~~~S FOR THE ELEMENTS OF THE F...

307KB Sizes 0 Downloads 9 Views

Volume 11, number

CHEMICAL PHYSICS LE’ITFXS

3

15 October

197 1

SE~-E~I~~AL.~OLE~~~ ORBITA_L,THEORY. THE ONE~ENT~ Q~~~~S FOR THE ELEMENTS OF THE FIRST AND SECOND TRANSITION SERIES L. DI SIP10

E. TONDELLO Laboratoriodi Chimicae TecnologiodeiRadioelementide1 C.N.R., Padova,IMy

G. DE MICHELIS Is&to di ChimfcaCeneraIesUniversit2di Venezia.It&y and L. OLEARI Isrihr~odi Chimica Fiska, Univerrira di Purma, &a& Received 15 July 1971

One-centre

are given which OLI be used

quaritities for the elements of the frost and second traadtion meti -ties one-centre integrals in semi-empirical MO calculat~oons.

instead of the conesponding

The main feature of the semi-empirical MO theory is the approx~ation of the one-centre integrals by certain quantities obtained from the valence state energies of the atoms. The valence state energies for an atom can be expressed by the following equation [l] : where C is a constant, necessary because of the different choice of the zero for the energy. Vi*, g$ are qusni i,j#i i titieo determined from the best FItfing of the valence state energ&& where tli are atomic orbital occupation numbers, Vi are core integrals andgii are quantities related to the We propose to use the-quantities 08 andgt instead Coulomb and exchange integrals by the expression of the corresponding integrals &$and g++in semi-empkicai MO caiculations. In fact these quantities fulfrl g[j = Jq t JKil
E=x niUi +4 C

nirtjgij ++ ;r)‘ni(ni-l)gii,

.’ ,. ,. ‘. .. _. .. ,” .. ‘. ,. ,: ,. y” ‘.,

(I)

~,’ ‘.

:, . .

.:: .” .: ;_ ....‘.( . . . . .; . ‘.‘,.,~.‘,_, ‘. ,.. .,., ,...: ~. .. ., :. ; ,.‘,. .’ :_ ,,:y .‘:’:...,,‘,, _‘ ~, ,11 _: : ..

: _, :

:

;.: .: _ ‘-.

iii

..

.,

y.:

;. ,’

; t

.,

. -; -c

:

‘, .iYd us

v.

Ti

r :

= ‘.

.. .’

h3.94

Co

43cl.59

Ni

‘570.43.



Cu

7303

-50.36

-61.22

-72.60

-40.37 l4.03 12.90

-49.24 14.70 1352

-58.54 15.31 14;14

12.23

12.82

13.41

14.00.

14.59

15.18 :

,14.25

14.85 15.64 7.96

15.45 16.27 8.25

il.64

gz=,x g&z ‘, ~B~y*z: gs+p

-141.57

-163.18

-84.50

-96.92

-109.86

-68.27 16.04 14.76

-78.43. 16.71

-89.b2 17.38’

15.38

r&o0

11.25 11.86 6.22

‘., ‘11.85 12.49 6.21

12.45 13.12 6.80

13.05 13.75 7.09

13x% 14.38 7.38

8.29 I.09 6.90

8.57

8.85 7.58 7:36

9.13 7.82 .7.59

9.4 1 8.06 7.82

9.69 8.30 8.05

9.97

10.25

7.34

8.54 8.28

8.79 8.51

7.26 7.05 (!LSEU (5.65>

7.50 7.28 (S.80) (s;.SQ) (5.091

7.98 . 7.74 (6.24) (6.103 (5.351

a.22 7.97 (6.46) C6.2S} (5.48)

8.46 8.20 (6.68) (6.40) (5.61)

8.70 8.42 (6.90) (6.55)

(4.96)

7.74 7.51 (6.02) (5.95). (5.22)

7.13

7.02 6.83 (5.361. (5.50) (4.83)

.’

-‘I--‘i~i~l5.

929.51

-31.93 13.36’ 12.28.

‘, ‘-101.92

‘.

-40.02

822,z

‘Semiempiri~

ud w;

315.#2 -83.88

..

Fe’

-23.92.

:

.c

;.

-30.20

8%S. gs.d

Q,P gx,y

218.48.

MO

:-67.03

.11.05

gxy,xs-y?’

: ,,

-51.37

l2.69 11.66

e;,z.x w,xy ‘&x,zy

.

“, :141.20

‘. -3tLsjO’::

Lvp : Bd,d

.’ Cr

15.01 7.67

_~

(s-7+)

Table 2 quaxhtieu (ii eV) for the elementsof the second trarkiti~n metal series from 2k to Ag Ru

w

Nti’

MO

Tc

76.62 :32.26

126.07 -44.41

193.54 -57.66

276.7

378.29

-72.01

-87.46 -66.32 -54.28

-is.sa

-37.25

-46.43

-56.12

-2i.92

-30.10

-37.72

-45.78

Pd

Rh 501.56

Ag

648.30

-104.01 Y-77.03

818.38

-121.66

-140.41

gd,d

10.38

10.96

11.54

f2.13

12.71

13.87

-99.98 -82.42 14.46

w,zx &‘,ay .gu;&

9.55

10.09

10.63

11.17

11.71.

12.25

12.79

13.33

‘, 9.05 9.22

9.56 9.74

10.07 10.26

11.09 Ii.30

11.60 11.82

12.11 12.34

9.72 6.42

kO.27 6.59’

10.82 6.77

10.58 10.78, il.37 6.94

11.92 7.11

12.47 7.29

13.02 $46

12.62 12.86 13.57 7.64

7.96 6.96

8.23 ~

8.49

9.29

7.4%

8.76 7.43

9.02

7.18 6.97 7.11

7.19 :

7.85’ 7.63.

7.84‘.

6.90

:%

..,:

:Sx~-j~,xy~

::&j gi.d

,,gz+ ‘,&2,x. Bzx,z: Sxy,Z’~ .g9;p gp,p

:.

I, 9.43

7.70.

" 6-51

‘6.74

6.32.

6.54

6.45

6.67

6.75 6.85.‘:

6;25

6.47.

6.69

(5.40),.(5,20) :

: ‘-

.’ ~5.53) (5.37f

'(4.55); (4.70)

-I'gx;y',, )

7.33

_

7.12 f6.08)”

-69.22

‘.

.13.29

I,

7.41. 7.56 .,

.. ,;7.33

(6.25) : (5.9E) .” (5.88) :. :’ (6.05) f5.71j .“.(4.85),,. “, (5.00) ‘. : (5.15)’ ,’ : ‘(5.30j _. (5.74)

” (5;54)

-88.25 -72.60

7,78

8.08 ..

7.55, .. ‘(6.42).

8.00’ 7.76 (6.59)

‘.

..(6.39) ':' (6.22)’ -(5.+j .:, : (5.60)

. : _,. ),,.’ .. : . . : ., ,_ ” ,’ ‘; I,.. .;. ., ,. ,.;:__” .,_)_’ ..: Y&tj~“::‘~~,‘,I y ‘.’ .-.,’ ‘. l.-‘.’ _: ‘. ,. .;,:-, ., .,, ‘, ,:;. ,_ ~.,, .” : ,. ;, ,: ,,:.‘.. : . .. ... ,y.,.;;: . . :: ,’ . _’ ..: ,:.;_ ,_(’ .. ‘..‘, ‘._“ .. ‘.. . ....’: ... .‘( .,.’ ._ .’ -: .: .,I : ., ‘ ., :. .’ .:, _. ,: ‘. :’ ‘.., :+:’ : .,..., .;: I’ ( _’ :. ._ ;,: ‘ , ‘ . _. .’ ,’ : :, ,’ ,’ :. ._ ,I _.. ; .‘, .’ .‘. ,. ‘. ., ., .’,.‘;‘._f ‘,‘._,‘, i) ,_._ . :. ,; ‘. .,

Volume ,ll, number 3

CHEMICAL PHYSICS LETTERS

The valence state energies have been calculated by means of the Slater-Condon parameters evaluated in our previous works [2]. The configurations dnB2sp, and dn-.“p2 have been excluded because of the rather poor accuracy of the corresponding Slater-Condon parameters. The calculations have been performed by applying the least squares method and by imposing the following restrictive conditions: (i) the quantities UF vary parabolically with the atomic number; (ii) the quantities g$ vary linearly with the atomic number; (iii) the quantities gr7 behave for axes transformations like the corresponding integrals gjj of eq. (1). The fist two conditions have been introduced, as in the evaluation.of the Slater-Condon parameters [2], in order to avoid irregular trends of the calculated

quantities with respect to the atomic number. Inthis way we have evahrated all the quantities Ur and g$ which are reported in tables 1 and 2 exe-qt

g&vi& and&. The latter (given in parentheses) have been evaluated in a second step by separately fitting the valence state

1.5October 1971

energies of the configurations dn-*sp and dnm2p2 calculated by means of the parameters given in our previous papers [2] ; Also in this calculation a condition of linear variation with atomic number has been . imposed.. The quantities obtained from this work are sufficiently accurate to permit the evaluation of’all‘the valence state energies for a given metal, beIonging to the oxidation‘states 0, +l, and +2 with a standard deviation smaller than 0.5 eV. This work has beerrsupported by C.N.R. (Italian National Research Council) and by NATO Contract No. 403.

References [l] L.Olti, LDi Sipio and G.De hfichelis. hfoI. phys. 10 (1966) 97. [2] E.TocdeUo, G.De Michelis. &Wari and LDiSipio, Coord. Chem. Rev. 2 (1967) 65; L.Di Sipio, E.TondelIo, G.De hfichetis and L.OIeari, Inorg. Chem. 9 (1970) 927. [3] R.Pariser and G.PY~, J. Chem. E%ys.21(1953) 466, 767.

289