Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)

Property	Value	Uncertainty	units	Reference	Comment
Hfg(298.15K)	-94.45	33.00	kJ mol-1	1989OPE/TEW9152	Entropy and HH from Gurvich.
Hfg(0K)	-92.00	33.00	kJ mol-1	1989OPE/TEW9152	Entropy and HH from Gurvich.
Entropy (298.15K)	232.62	8.40	J K-1 mol-1	Gurvich
Integrated Heat Capacity (0 to 298.15K)	11.12		kJ mol-1	Gurvich
Heat Capacity (298.15K)	42.99		J K-1 mol-1	webbook	Entropy and HH from Gurvich. Cp from Webbook

Information can also be found for this species in the NIST Chemistry Webbook

Vibrational levels (cm^-1)

Mode Number	Symmetry	Frequency (cm-1)	Frequency Reference	Intensity (km mol-1)	Int. unc.	Intensity Reference	Comment
2	Σ	750	VEEL5
3	Π	188	VEEL5

Calculated vibrational frequencies for MgOH (magnesium hydroxide).

Rotational Constants (cm^-1)
See section I.F.4 to change rotational constant units

A	B	C	reference	comment
	0.50158		1999App/And:10919

Calculated rotational constants for MgOH (magnesium hydroxide).

Product of moments of inertia
33.60937	amu Å2		5.581055E-39	gm cm2

Geometric Data

Point Group C_∞v

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees

Description	Value	unc.	Connectivity				Reference	Comment
			Atom 1	Atom 2	Atom 3	Atom 4
rMgO	1.767		1	2			1999App/And:10919	re structure
rOH	0.940		1	3			1992Bar/And:225	re
aHOMg	180		2	1	3		1999App/And:10919	quasilinear

Cartesians

Atom	x (Å)	y (Å)	z (Å)
O1	0.0000	0.0000	0.0000
Mg2	0.0000	0.0000	1.7670
H3	0.0000	0.0000	-0.9400

Atom - Atom Distances
Distances in Å

	O1	Mg2	H3
O1		1.7670	0.9400
Mg2	1.7670		2.7070
H3	0.9400	2.7070

Calculated geometries for MgOH (magnesium hydroxide).

Experimental Bond Angles (degrees) from cartesians

atom1	atom2	atom3	angle		atom1	atom2	atom3	angle
Mg2	O1	H3	180.000

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond

Bond Type	Count
H-O	1
O-Mg	1

Connectivity

Atom 1	Atom 2
O1	Mg2
O1	H3

Electronic energy levels (cm^-1)

Energy (cm-1)	Degeneracy	reference	description
0	2		2A'

Ionization Energies (eV)

Ionization Energy	I.E. unc.	vertical I.E.	v.I.E. unc.	Electron Affinity	E.A. unc.	reference
7.500	0.300					webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment
Calculated electric dipole moments for MgOH (magnesium hydroxide).
Electric quadrupole moment
Calculated electric quadrupole moments for MgOH (magnesium hydroxide).

References
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squib	reference	DOI
1989OPE/TEW9152	Operti, L; Tews, EC; MacMahon, TJ; Freiser, BS, Thermochemical properties of Gas-Phase MgOH and MgO determined by FTMS. JACS 111, 9152, 1989	10.1021/ja00208a002
1992Bar/And:225	Barclay, W.L.; Anderson, M.A.; Ziurys, L.M. "The millimeter-wave spectrum of the MgOH radical." Chemical Physics Letters. 196, 225-232 (1992)	10.1016/0009-2614(92)85959-E
1999App/And:10919	AJ Apponi, MA Anderson, LM Ziurys "High resolution spectroscopy of MgOH (X 2Sigma+) in its v2 mode: Further evidence for quasilinearity" J. Chem. Phys. 111, 10919, 1999	10.1063/1.480455
Gurvich	Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989	10.1351/pac198961061027
VEEL5	M.E. Jacox, Vibrational and Electronic Energy Levels of Polyatomic Transient Molecules, J. Phys. Chem.Ref. Data, Monograph 3 (1994) (updated data in NIST Chemistry Webbook - http://webbook.nist.gov/chemistry/
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)

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