hw_9

•Calculate the structures and atomization energies (AE) of following molecules with following methods then compare with the experimental values.

molecule H2Li2B2C2N2O2F2P2S2Cl2

method

MP2/6-31+G(d,p)

B3LYP/aug-cc-pVTZ

CCSD(T)/aug-cc-pVTZ  

Atomization Energies

 

⇒實驗值來源 (the Source of Experimental Values)

(單位:Kcal/mol)

atomization energies

MP2

6-31+G(d,p)

B3LYP

aug-cc-pVTZ

CCSD(T)

aug-cc-pVTZ

Exp

( De )

H2

101.2

110.1

108.6

109.5

Li2

14.3

20.9

23.8

24.6

B2

39

34.4

47

67.1

C2

91.1

103.7

103.7

145.7

N2

215.6

228.9

217.7

228.5

O2

86.8

84.7

85.1

120.0

F2

34.8

37.1

36.4

38.2

P2

93.7

114.1

107

117.1

S2

60.4

78.3

80.4

101.7

Cl2

41.9

54

56.8

58.0

Absolute error of atomization energy

 

MP2,6-31+G(d,p)

B3LYP,aug-cc-pVTZ

CCSD,aug-cc-pVTZ

H2

8.3

0.6

0.9

Li2

10.3

3.7

0.8

B2

28.1

32.7

20.1

C2

54.6

42.0

42.0

N2

12.9

0.4

10.8

O2

33.2

35.3

34.9

F2

3.4

1.1

1.8

P2

23.4

3.0

10.1

S2

41.3

23.4

21.3

Cl2

16.1

4.0

1.2

a

Structure-bond length

 

MP2

6-31+G(d,p)

B3LYP

aug-cc-pVTZ

CCSD

aug-cc-pVTZ

Exp( De )

H2

0.734

0.743

0.743

0.741

Li2

2.787

2.699

2.700

2.673

B2

1.898

1.937

1.909

1.59

C2

1.396

1.384

1.391

1.243

N2

1.131

1.091

1.104

1.213

O2

1.274

1.205

1.226

1.208

F2

1.433

1.397

1.418

1.412

P2

1.934

1.895

1.916

1.893

S2

1.939

1.914

1.931

1.889

Cl2

2.018

2.023

2.020

1.988


Absolute error

 

MP2

6-31+G(d,p)

B3LYP

aug-cc-pVTZ

CCSD

aug-cc-pVTZ

H2

0.007

0.002

0.002

Li2

0.114

0.026

0.027

B2

0.308

0.347

0.319

C2

0.153

0.141

0.148

N2

0.082

0.122

0.109

O2

0.066

0.003

0.018

F2

0.021

0.015

0.006

P2

0.041

0.002

0.023

S2

0.05

0.025

0.042

Cl2

0.03

0.035

0.032

 

s

•Calculate the standard enthalpy of formation (ΔH°f) of AHn (A = H~Ne) with following methods then compare with the experimental values.

optimization:MP2/aug-cc-pVTZ

single point energy:CCSD(T)/aug-cc-pVTZ

⇒實驗值來源 (the Source of Experimental Values)

 

 

MP2/aug-cc-pVTZ

CCSD(T)/aug-cc-pVTZ

//MP2/aug-cc-pVTZ

EXP

H2

5.8

1.1

0

LiH

39.6

34.4

33.6

BeH2

41.6

42.5

30

BH3

29.1

27.8

21

CH4

-8.0

-28.4

-17.8

NH3

-2.7

-3.8

-11

H2O

-57

-53

-57.8

HF

-67.6

-63.2

-65.3

 

s

S