silicon based life forms peter ballo
DESCRIPTION
Silicon Based Life Forms Peter Ballo. Cluster technique. Lattice constant. Bulk modulus. Cohesive energy. Vacancy formation energy. DLTS spectroscopy. Lattice constant. a=5.44 Å. Bulk modulus. Cohesive energy. - PowerPoint PPT PresentationTRANSCRIPT
Silicon Based Life FormsSilicon Based Life Forms
Peter BalloPeter Ballo
Cluster technique
Lattice constant
Bulk modulus
Cohesive energy
Vacancy formation energy
DLTS spectroscopy
5.43 5.44 5.45 5.46 5.47 5.48-9644.6
-9644.5
-9644.5
-9644.4
-9644.4
-9644.3
-9644.3
-9644.2
Ene
rgy
(eV
)
Lattice constant (A)
Lattice constant
a=5.44 Å
Bulk modulus
5.43 5.44 5.45 5.46 5.47 5.48-9644.6
-9644.5
-9644.5
-9644.4
-9644.4
-9644.3
-9644.3
-9644.2
Ene
rgy
(eV
)
Lattice constant (A)
2
2
0 dV
EdVB
GPaB 1.96
Cohesive energy
Cluster Energy (eV)
Si9H15 -954,36
Si102H82 -9644.87
Element Lattice energy (eV)
Silicon -83.84
Hydrogen -13.32
eVEc 66.4 V-79.17738e)(1 SiE
)(1 SiEEE Lc
Ecoh=-(Total energy of one free atom – Total energy of cluster/Number of atoms)
Vacancy formation energy
Lv EnEnEE )1()(
eVEv 30.3
Method ao(Å) B(GPa) Ec(eV) Ev(eV)
cluster 5.44 96.1 -4.66 3.30
ab initio 5.39(a) 100.0(a) -4.51(b) 3.38(c)
experiment 5.43(d) 98.8(d) -4.63(d)
Summary
(a) Pesola, J.von Boehm, T.Mattila, and R.M.Nieminen, Phys.Rev.B 60,11 449 (1998). (b) X.-P. Li, D.M.Ceperley, and R.M.Martin, Phys.Rev.B 44, 10 929 (1991). (c) S.J.Clark and G.J.Ackland, Phys.Rev.B 48, 10 899 (1993). (d) Ch. Kittel, Introduction to Solid State Physics (Wiley, New York, 1996).
1,0 1,5 2,0 2,5 3,0 3,5 4,0-0,05
0,00
0,05
0,10
0,15
0,20
0,25
0,30E
nerg
y (e
V)
Distance (A)
Korekčná funkcia v MNDOKorekčná funkcia v MNDO
DO
S (
arb.
uni
ts)
Energy (eV)
Oxygen defectP.Ballo and L.Harmatha, Phys.Rev.B 68, 153201 (2003).
eVEE v 6.1 eVEE v 05.0
B
O
C
A
defaults used first point
MOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDEN
A
B
C
O
defaults used first point
MOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDENMOLDEN
A centrum H centrumA centrum H centrum
E(NO)=-2.87eV E(2NO)=-5.52eV