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Lead iodide


Gas phase thermochemistry data

Go To: Top, Constants of diatomic molecules, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Quantity Value Units Method Reference Comment
Deltafgas25.750kcal/molReviewChase, 1998Data last reviewed in December, 1973
Quantity Value Units Method Reference Comment
gas,1 bar66.953cal/mol*KReviewChase, 1998Data last reviewed in December, 1973

Gas Phase Heat Capacity (Shomate Equation)

Cp° = A + B*t + C*t2 + D*t3 + E/t2
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
    Cp = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. - 6000.
A 8.942680
B -0.044785
C 0.165290
D -0.016872
E -0.004233
F 23.07090
G 77.75619
H 25.75000
ReferenceChase, 1998
Comment Data last reviewed in December, 1973

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through July, 1977

Symbols used in the table of constants
SymbolMeaning
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for (208)Pb127I
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
B (2Sigma) 33488.0 198.7 H 0.35 1        B larrow X V 33507.1 2 H
missing citation
A (1/2) 20529.0 142.0 2 H 1.50        A lrarrow X R 20519.4 H
missing citation
X (2Pi1/2) 0 160.5 H 0.25         

Notes

1Diffuse bands (prediss.)
2Vibrational numbering uncertain.
3See the discussion in Wieland and Newburgh, 1952.

References

Go To: Top, Gas phase thermochemistry data, Constants of diatomic molecules, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Wieland and Newburgh, 1952
Wieland, K.; Newburgh, R., Uber einige neue Bandenspektren der Radikale PbCl, PbBr und PbJ, Helv. Phys. Acta, 1952, 25, 87. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Constants of diatomic molecules, References