	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for NH₂CONH₂ (Urea)

using model chemistry: HF/3-21G

19 10 17 12 22

States and conformations

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C2	¹A
1	2	no	CS	¹A^'
1	3	no	C2V	¹A₁

Conformer 1 (C2)

Jump to S1C2 S1C3

Energy calculated at HF/3-21G

	hartrees
Energy at 0K	-222.736831
Energy at 298.15K	-222.743097
HF Energy	-222.736831
Nuclear repulsion energy	124.483403

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at HF/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3926	3555	72.96
2	A	3803	3444	9.57
3	A	1901	1721	483.92
4	A	1823	1651	0.07
5	A	1263	1144	3.36
6	A	1020	924	10.12
7	A	568	514	0.00
8	A	529	479	2.71
9	A	256	232	0.00
10	B	3922	3552	36.71
11	B	3795	3437	77.36
12	B	1794	1625	194.29
13	B	1525	1381	366.44
14	B	1101	997	16.86
15	B	896	811	302.41
16	B	618	560	208.16
17	B	612	555	19.73
18	B	546	494	508.61

Unscaled Zero Point Vibrational Energy (zpe) 14949.0 cm^-1
Scaled (by 0.9056) Zero Point Vibrational Energy (zpe) 13537.8 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at HF/3-21G

A	B	C
0.37595	0.35311	0.18208

See section I.F.4 to change rotational constant units

Geometric Data calculated at HF/3-21G

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.142
O2	0.000	0.000	1.362
N3	0.000	1.147	-0.597
N4	0.000	-1.147	-0.597
H5	0.000	2.011	-0.103
H6	0.001	1.163	-1.591
H7	-0.000	-2.011	-0.103
H8	-0.001	-1.163	-1.591

Atom - Atom Distances (Å)

	C1	O2	N3	N4	H5	H6	H7	H8
C1		1.2200	1.3648	1.3648	2.0261	2.0872	2.0261	2.0872
O2	1.2200		2.2704	2.2704	2.4884	3.1738	2.4884	3.1738
N3	1.3648	2.2704		2.2945	0.9952	0.9937	3.1968	2.5151
N4	1.3648	2.2704	2.2945		3.1968	2.5151	0.9952	0.9937
H5	2.0261	2.4884	0.9952	3.1968		1.7122	4.0224	3.5058
H6	2.0872	3.1738	0.9937	2.5151	1.7122		3.5058	2.3266
H7	2.0261	2.4884	3.1968	0.9952	4.0224	3.5058		1.7122
H8	2.0872	3.1738	2.5151	0.9937	3.5058	2.3266	1.7122

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	N3	H5	117.444	C1	N3	H6	123.725
C1	N4	H7	117.444	C1	N4	H8	123.725
O2	C1	N3	122.799	O2	C1	N4	122.799
N3	C1	N4	114.403	H5	N3	H6	118.831
H7	N4	H8	118.831

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G Charges (e)

Number	Element	Mulliken
1	C	1.152
2	O	-0.673
3	N	-0.949
4	N	-0.949
5	H	0.367
6	H	0.342
7	H	0.367
8	H	0.342

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	-4.657	4.657
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-25.144	0.008	0.000
y	0.008	-16.349	0.000
z	0.000	0.000	-24.306

Traceless
	x	y	z
x	-4.816	0.008	0.000
y	0.008	8.376	0.000
z	0.000	0.000	-3.559

Polar
3z²-r²	-7.119
x²-y²	-8.795
xy	0.008
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	0.994	0.000	0.000
y	0.000	3.465	0.000
z	0.000	0.000	3.933

<r²> (average value of r²) Å²

<r²>	67.960
(<r²>)^1/2	8.244

Conformer 2 (CS)

Jump to S1C1 S1C3

Energy calculated at HF/3-21G

	hartrees
Energy at 0K	-222.736831
Energy at 298.15K	-222.743096
HF Energy	-222.736831
Nuclear repulsion energy	124.483434

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at HF/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A'	3926	3555	72.95
2	A'	3803	3444	9.58
3	A'	1901	1721	483.96
4	A'	1823	1651	0.07
5	A'	1263	1144	3.36
6	A'	1020	924	10.13
7	A'	896	811	302.32
8	A'	618	560	208.26
9	A'	546	494	508.63
10	A'	529	479	2.71
11	A"	3922	3552	36.72
12	A"	3795	3437	77.33
13	A"	1794	1625	194.26
14	A"	1525	1381	366.45
15	A"	1101	997	16.86
16	A"	612	555	19.71
17	A"	568	514	0.00
18	A"	255	231	0.00

Unscaled Zero Point Vibrational Energy (zpe) 14948.8 cm^-1
Scaled (by 0.9056) Zero Point Vibrational Energy (zpe) 13537.6 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at HF/3-21G

A	B	C
0.37593	0.35312	0.18208

See section I.F.4 to change rotational constant units

Geometric Data calculated at HF/3-21G

Point Group is C_s

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.142	0.000
O2	-0.000	1.362	0.000
N3	0.000	-0.597	1.147
N4	0.000	-0.597	-1.147
H5	0.000	-0.103	2.011
H6	0.000	-1.591	1.163
H7	0.000	-0.103	-2.011
H8	0.000	-1.591	-1.163

Atom - Atom Distances (Å)

	C1	O2	N3	N4	H5	H6	H7	H8
C1		1.2200	1.3648	1.3648	2.0261	2.0872	2.0261	2.0872
O2	1.2200		2.2705	2.2705	2.4885	3.1738	2.4885	3.1738
N3	1.3648	2.2705		2.2944	0.9952	0.9937	3.1968	2.5150
N4	1.3648	2.2705	2.2944		3.1968	2.5150	0.9952	0.9937
H5	2.0261	2.4885	0.9952	3.1968		1.7122	4.0224	3.5056
H6	2.0872	3.1738	0.9937	2.5150	1.7122		3.5056	2.3265
H7	2.0261	2.4885	3.1968	0.9952	4.0224	3.5056		1.7122
H8	2.0872	3.1738	2.5150	0.9937	3.5056	2.3265	1.7122

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	N3	H5	117.445	C1	N3	H6	123.725
C1	N4	H7	117.445	C1	N4	H8	123.725
O2	C1	N3	122.801	O2	C1	N4	122.801
N3	C1	N4	114.398	H5	N3	H6	118.830
H7	N4	H8	118.830

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G Charges (e)

Number	Element	Mulliken
1	C	1.152
2	O	-0.673
3	N	-0.949
4	N	-0.949
5	H	0.367
6	H	0.342
7	H	0.367
8	H	0.342

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.002	-4.657	0.000	4.657
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-25.144	0.001	0.000
y	0.001	-24.306	0.000
z	0.000	0.000	-16.349

Traceless
	x	y	z
x	-4.816	0.001	0.000
y	0.001	-3.559	0.000
z	0.000	0.000	8.375

Polar
3z²-r²	16.751
x²-y²	-0.838
xy	0.001
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	0.994	-0.000	0.000
y	-0.000	3.933	0.000
z	0.000	0.000	3.464

<r²> (average value of r²) Å²

<r²>	67.960
(<r²>)^1/2	8.244

Conformer 3 (C2V)

Jump to S1C1 S1C2

Energy calculated at HF/3-21G

	hartrees
Energy at 0K	-222.736831
Energy at 298.15K	-222.743096
HF Energy	-222.736831
Nuclear repulsion energy	124.481337

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at HF/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	3926	3555	72.93
2	A₁	3803	3444	9.59
3	A₁	1901	1721	483.94
4	A₁	1823	1651	0.10
5	A₁	1263	1144	3.34
6	A₁	1020	924	10.15
7	A₁	529	479	2.71
8	A₂	568	514	0.00
9	A₂	256	231	0.00
10	B₁	896	811	302.19
11	B₁	618	560	206.36
12	B₁	545	494	510.72
13	B₂	3922	3552	36.81
14	B₂	3795	3437	77.26
15	B₂	1794	1625	194.12
16	B₂	1524	1380	366.42
17	B₂	1101	997	16.93
18	B₂	612	555	19.72

Unscaled Zero Point Vibrational Energy (zpe) 14948.3 cm^-1
Scaled (by 0.9056) Zero Point Vibrational Energy (zpe) 13537.2 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at HF/3-21G

A	B	C
0.37595	0.35307	0.18208

See section I.F.4 to change rotational constant units

Geometric Data calculated at HF/3-21G

Point Group is C_2v

Cartesians (Å)

Atom	y (Å)	z (Å)
C1	0.000	0.142
O2	0.000	1.362
N3	1.147	-0.597
N4	-1.147	-0.597
H5	2.011	-0.103
H6	1.163	-1.591
H7	-2.011	-0.103
H8	-1.163	-1.591

Atom - Atom Distances (Å)

	C1	O2	N3	N4	H5	H6	H7	H8
C1		1.2199	1.3649	1.3649	2.0262	2.0871	2.0262	2.0871
O2	1.2199		2.2705	2.2705	2.4884	3.1737	2.4884	3.1737
N3	1.3649	2.2705		2.2946	0.9952	0.9937	3.1970	2.5151
N4	1.3649	2.2705	2.2946		3.1970	2.5151	0.9952	0.9937
H5	2.0262	2.4884	0.9952	3.1970		1.7123	4.0225	3.5057
H6	2.0871	3.1737	0.9937	2.5151	1.7123		3.5057	2.3263
H7	2.0262	2.4884	3.1970	0.9952	4.0225	3.5057		1.7123
H8	2.0871	3.1737	2.5151	0.9937	3.5057	2.3263	1.7123

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	N3	H5	117.444	C1	N3	H6	123.714
C1	N4	H7	117.444	C1	N4	H8	123.714
O2	C1	N3	122.799	O2	C1	N4	122.799
N3	C1	N4	114.401	H5	N3	H6	118.842
H7	N4	H8	118.842

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G Charges (e)

Number	Element	Mulliken
1	C	1.152
2	O	-0.673
3	N	-0.949
4	N	-0.949
5	H	0.367
6	H	0.342
7	H	0.367
8	H	0.342

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	-4.656	4.656
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-25.144	0.000	0.000
y	0.000	-16.350	0.000
z	0.000	0.000	-24.305

Traceless
	x	y	z
x	-4.816	0.000	0.000
y	0.000	8.374	0.000
z	0.000	0.000	-3.558

Polar
3z²-r²	-7.116
x²-y²	-8.794
xy	0.000
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	0.994	0.000	0.000
y	0.000	3.465	0.000
z	0.000	0.000	3.933

<r²> (average value of r²) Å²

<r²>	67.962
(<r²>)^1/2	8.244

All results from a given calculation for NH2CONH2 (Urea)

using model chemistry: HF/3-21G

States and conformations

Conformer 1 (C2)

Conformer 2 (CS)

Conformer 3 (C2V)

All results from a given calculation for NH₂CONH₂ (Urea)