Rep:Mod:sy4615

Ammonia

	NH3
r(E-X)
θ(X-E-X)

nh3 optimisation
File Name    SHYANT_NH3_OPTF_POP
File Type    .log
Calculation Type    FREQ
Calculation Method    RB3LYP
Basis Set    6-31G(d,p)
Charge    0
Spin    Singlet
E(RB3LYP)    -56.55776873     a.u.
RMS Gradient Norm    0.00000323     a.u.
Imaginary Freq
Dipole Moment    1.8465     Debye
Point Group    C3V
Job cpu time:       0 days  0 hours  0 minutes  9.0 seconds. 

test molecule

The charge on the nitrogen atom in ammonia: -1.125 The charge on the hydrogen atom in ammonia: 0.375. The expected value for charge on nitrogen is about three times more than on hydrogen because the electronegative of nitrogen is also triple the value of hydrogen.

Basic summary for N2

Title Card Required
File Name	SHyant_n2_optf_pop
File Type	.log
Calculation Type	FREQ
Calculation Method	RB3LYP
Basis Set	6-31G(d,p)
Charge	0
Spin	Singlet
E(RB3LYP)	-109.52412868	 a.u.
RMS Gradient Norm	0.00000060	 a.u.
Imaginary Freq	0
Dipole Moment	0.0000	 Debye
Point Group	D*H
Job cpu time:       0 days  0 hours  0 minutes  7.0 seconds.

The frequency is 2457.33.

Basic summary for H2

Title Card Required
File Name	SHyant_h2_optf_pop
File Type	.log
Calculation Type	FREQ
Calculation Method	RB3LYP
Basis Set	6-31G(d,p)
Charge	0
Spin	Singlet
E(RB3LYP)	-1.17853936	 a.u.
RMS Gradient Norm	0.00000017	 a.u.
Imaginary Freq	0
Dipole Moment	0.0000	 Debye
Point Group	D*H
Job cpu time:       0 days  0 hours  0 minutes  6.0 seconds.

The frequency is 4465.68.

   E(NH3)=-56.55776873	 
   2*E(NH3)=-113.11553746
   E(N2)=-109.52412868	 
   E(H2)=-1.17853936
   3*E(H2)=-3.53561808
   ΔE=2*E(NH3)-[E(N2)+3*E(H2)]=-0.0557907

the energy for converting hydrogen and nitrogen gas into ammonia gas is -146.81 kj/mol. It is more stable in the ammonia form than in the reactant mixture.

Cyanide

test molecule

Title Card Required
File Name	SHyantt_cn-_optf_pop
File Type	.log
Calculation Type	FREQ
Calculation Method	RB3LYP
Basis Set	6-31G(d,p)
Charge	-1
Spin	Singlet
E(RB3LYP)	-92.82453153	 a.u.
RMS Gradient Norm	0.00000704	 a.u.
Imaginary Freq	0
Dipole Moment	0.5236	 Debye
Point Group	C*V
Job cpu time:       0 days  0 hours  0 minutes  8.0 seconds.

The charge on the nitrogen atom in cyanide ion is -0.754 and the charge on the carbon atom is -0.246

This is the lowest energy sigma molecular orbital in the molecule, it is at at an energy well of -14.00393 au and are not very involved with chemical bonding.

These are the 3-sigma bonding MO and the 4-sigma anitibonding MO. They form by combining the 2s valence AOs in carbon and nitrogen atom. The energy of these orbitals are much more higher, therefore they are very involved in the chemical bonding.

These are the pi bonding orbitals, they have exactly the same energy of -0.01696 au,because there are two pi AOs on each atom that are perpendicular to the bond.

Formed by mixing of the 5 sigma and the 3 sigma MOs, the 5 sigma orbital goes up in energy and the become the HOMO in the molecules. The mixing also cause the distortion of the shape of the MOs.