RichardZhang

Borane

1.RB3LYP/3-21G:

2.RB3LYP/6-31g:

The optimisation file is liked to here

BH3

Vibrational Information

Mode	Vibration	Intensity	Symmetry	IR Active	Type
1	1163	93	A2'	Yes	out-of-plane bend
2	1213	14	E'	Yes	bend
3	1213	14	E'	Yes	bend
4	2582	0	A1'	No	symmetric stretch
5	2715	126	E'	Yes	asymmetric stretch
6	2715	126	E'	Yes	asymmetric stretch

There are less than six peaks in the spectrum even though there are obvious six vibrations. This is because the translation modes are degenerate each other, such as mode 2 and mod 3, mode 5 and mode 6.

Ammonia

RB3LYP/6-31g:

The optimisation file is liked to here

Ammonia

Vibrational Information

Mode	Vibration	Intensity	Symmetry	IR Active	Type
1	1694	145	A	Yes	out-of-plane bend
2	1694	13	E	Yes	bend
3	1694	13	E	Yes	bend
4	3461	1	A1	No	symmetric stretch
5	3589	0	E	No	asymmetric stretch
6	3589	0	E	No	asymmetric stretch

Ammonia Borane

RB3LYP/6-31g:

The optimisation file is liked to here

Ammonia Borane

Association Energy

E(NH3)=-56.55776863 a.u ≈ -1.48492x10^5 kJ/mol

E(BH3)=-26.61532360 a.u ≈ -6.9879x10^4 kJ/mol

E(NH3BH3)=-83.22469012 a.u ≈ -2.18506x10^5 kJ/mol

ΔE = E(NH3BH3)-[E(BH3)+E(NH3)] = -2.18506x10^5+(6.9879x10^4+1.48492x10^5) ≈ -135 kJ/mol

The value of association energy is a negative value, which means the B-N dative bond is stronger than the ?

Borone tribromide

1. RB3LYP/GEN:

The optimisation file is liked to here

Boron tribromide

Vibrational Information

Mode	Vibration	Intensity	Symmetry	IR Active	Type
1	156	145	E'	NO	asymmetric stretch
2	156	13	E'	NO	asymmetric stretch
3	268	13	A1'	NO	symmetric stretch
4	378	1	A2	Yes	out-of-plane bend
5	763	0	E'	Yes	bend
6	763	0	E'	Yes	bend

The pps-optimisation of BBr3: DOI:10042/202437

The pps-frequency of BBr3: DOI:10042/202439