Phosphorus dimer

Formula: P₂
Molecular weight: 61.947524
IUPAC Standard InChI: InChI=1S/P2/c1-2
IUPAC Standard InChIKey: FOBPTJZYDGNHLR-UHFFFAOYSA-N
CAS Registry Number: 12185-09-0
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Permanent link for this species. Use this link for bookmarking this species for future reference.
Information on this page:
Other data available:
Options:
- Switch to calorie-based units

Constants of diatomic molecules

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

Data collected through May, 1977

Symbols used in the table of constants
Symbol	Meaning
State	electronic state and / or symmetry symbol
T_e	minimum electronic energy (cm^-1)
ω_e	vibrational constant – first term (cm^-1)
ω_ex_e	vibrational constant – second term (cm^-1)
ω_ey_e	vibrational constant – third term (cm^-1)
B_e	rotational constant in equilibrium position (cm^-1)
α_e	rotational constant – first term (cm^-1)
γ_e	rotation-vibration interaction constant (cm^-1)
D_e	centrifugal distortion constant (cm^-1)
β_e	rotational constant – first term, centrifugal force (cm^-1)
r_e	internuclear distance (Å)
Trans.	observed transition(s) corresponding to electronic state
ν₀₀	position of 0-0 band (units noted in table)

Diatomic constants for ³¹P₂
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
Carroll and Mitchell's Rydberg series V_n converging to F ²Σ_u⁺(v=0):
... 4σ_u 5σ_g² 2π_u⁴ nsσ_g 1	v=125225 - R/(n-1.86)², n=5(v₅),6...16. Similar series with v'=1.
... 4σ_u 5σ_g² 2π_u⁴ nsσ_g 1	↳Carroll and Mitchell, 1975
V₅ (¹Σ_u⁺)	114085	[789]									V₅ ← X	114090
V₅ (¹Σ_u⁺)	↳Carroll and Mitchell, 1975
... 4σ_u² 5σ_g 2π_u⁴	2
... 4σ_u² 5σ_g 2π_u⁴	↳missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
... 4σ_u² 5σ_g 2π_u⁴ nfπ_u	3
... 4σ_u² 5σ_g 2π_u⁴ nfπ_u	↳missing citation
... 4σ_u² 5σ_g 2π_u⁴ nfσ_u	4
... 4σ_u² 5σ_g 2π_u⁴ nfσ_u	↳missing citation
... 4σ_u² 5σ_g 2π_u⁴ npπ_u	5
... 4σ_u² 5σ_g 2π_u⁴ npπ_u	↳missing citation
... 4σ_u² 5σ_g 2π_u⁴ npσ_u	6
... 4σ_u² 5σ_g 2π_u⁴ npσ_u	↳missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
... 4σ_u² 5σ_g² 2π_u³	7
... 4σ_u² 5σ_g² 2π_u³	↳missing citation
... 4σ_u² 5σ_g² 2π_u³ ndδ_g ?	8
... 4σ_u² 5σ_g² 2π_u³ ndδ_g ?	↳missing citation
... 4σ_u² 5σ_g² 2π_u³ ndπ_g	9
... 4σ_u² 5σ_g² 2π_u³ ndπ_g	↳missing citation
... 4σ_u² 5σ_g² 2π_u³ ndσ_g	10
... 4σ_u² 5σ_g² 2π_u³ ndσ_g	↳missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
... 4σ_u² 5σ_g² 2π_u³ nsσ_g	11
... 4σ_u² 5σ_g² 2π_u³ nsσ_g	↳missing citation
Unclassified bands 79700 - 84500 cm^-1.
↳Carroll and Mitchell, 1975
U	83362	[551] H 12									U ← X R	83248 H
U	↳missing citation
G₆ (¹Σ_u⁺)	81327	[723] 13									G₆ ← X R	81299 H
G₆ (¹Σ_u⁺)	↳Creutzberg, 1966; Carroll and Mitchell, 1975
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
T	80992	[713.1] H 14									T ← X R	80958.5 H
T	↳Creutzberg, 1966; missing citation
S ¹Σ_u⁺	(80840)				B₁=0.2783					r₁=1.978	S ← X R	81453.89 15 Z
S ¹Σ_u⁺	↳Creutzberg, 1966; Carroll and Mitchell, 1975
R₄ (¹Π_u)	80115	[740] 16									R₄ ← X	80095
R₄ (¹Π_u)	↳Carroll and Mitchell, 1975
Q (¹Π_u)	(79860)	[617.6] H 17									Q ← X R	79779.5₃ H
Q (¹Π_u)	↳Creutzberg, 1966; Carroll and Mitchell, 1975
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
P₄ (¹Σ_u⁺)	(79827) 18										P₄ ← X	79804
P₄ (¹Σ_u⁺)	↳Carroll and Mitchell, 1975
M₄ (¹Σ_u⁺)	(78271)	(705)	(5) 19								M₄ ← X R	(78233) 20
M₄ (¹Σ_u⁺)	↳Carroll and Mitchell, 1975
H₅ (¹Π_u)	(78256) 21										H₅ ← X	78233
H₅ (¹Π_u)	↳Carroll and Mitchell, 1975
K₄ (¹Π_u)	(77968)	[732] 13									K₄ ← X	77944
K₄ (¹Π_u)	↳Carroll and Mitchell, 1975
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
O	77475	529 H	2								O ← X R	77349 H
O	↳missing citation
N ¹Σ_u⁺	77286.₇	[641.76] Z	(29.7)		0.2984 22	0.0050₄		[3.1E-7]		1.909₉	N ← X R	77240.2₃ Z
N ¹Σ_u⁺	↳Creutzberg, 1966; Carroll and Mitchell, 1975
L (¹Π_u)	73593	[672.2] H									L ← X R	73539.3 H
L (¹Π_u)	↳Creutzberg, 1966; Carroll and Mitchell, 1975
E₅ (¹Π_u)	73385	685 H	2.₇								E₅ ← X R	73337
E₅ (¹Π_u)	↳Carroll and Mitchell, 1975
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
M ¹Σ_u⁺	73168.0	684.0 23 H	2.9₇		0.2802 23	0.0016				1.971	M ← X R	73119.6 23 H
M ¹Σ_u⁺	↳Creutzberg, 1966; Carroll and Mitchell, 1975
K ¹Π_u	72288	[701.7] H^Q	(5)		[0.2704] 24 22					[2.006]	K ← X R	72253.3 Z
K ¹Π_u	↳Creutzberg, 1966; Carroll and Mitchell, 1975
Numerous diffuse irregularly spaced "lines" 69900 - 70400 cm^-1, no assignments.
↳Creutzberg, 1966
H (¹Π_u)	(68960) 25										H ← X	68940
H (¹Π_u)	↳Creutzberg, 1966; Carroll and Mitchell, 1975
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
I ¹Π_u	[68849.3]				[0.2541]			[2.₅E-7]		[2.070]	I ← X R	68459.6₃ Z
I ¹Π_u	↳Creutzberg, 1966
G ¹Σ_u⁺	66313.37	694.12 Z	4.18₂		0.29730 22	0.00195		[2.25E-7]		1.9135	G ↔ X R	66269.71 Z
G ¹Σ_u⁺	↳Dressler, 1955; missing citation
E ¹Π_u	59446.21	700.66 H^Q	2.92		[0.2807₂] 22			[1.84E-7]		[1.969₂]	E ↔ X 26 R	59406.14 Z
E ¹Π_u	↳Dressler, 1955; missing citation
B ¹Π_u	50845.9	[358.96] 27 Z	28		[0.2268] 27	29		[3.2E-7]		[2.191]	B → A R	16203.7₁ 27 Z
B ¹Π_u	↳Malicet, Brion, et al., 1973; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
c ³Π_u2	47176.8	393.67 Z	3.849 30	-.0915	0.2190 31	0.0024		2.5E-7		2.229	c → b 32 R	18721.5 Z
c ³Π_u2	↳Brion, da Paz, et al., 1971; missing citation; Carroll and Nulty, 1976; missing citation
c ³Π_u1	47159.1	393.67 Z	3.849 30	-.0915	0.2190 31	0.0024		2.5E-7		2.229	c → b 32 R	18836.4 Z
c ³Π_u1	↳Brion, da Paz, et al., 1971; missing citation; Carroll and Nulty, 1976; missing citation
c ³Π_u0	47139.2	393.67 Z	3.849 30	-.0915	0.2190 31	0.0024		2.5E-7		2.229	c → b 32 R	18944.6 Z
c ³Π_u0	↳Brion, da Paz, et al., 1971; missing citation; Carroll and Nulty, 1976; missing citation
C ¹Σ_u⁺	46941.26	473.93 Z	2.340 33	0.0066	0.24211 34 22	0.00175	3.₃E-6	2.57E-7		2.1204	C ↔ X R	46787.97 Z
C ¹Σ_u⁺	↳missing citation; missing citation; Marais and Verleger, 1950; Creutzberg, 1966; missing citation; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
A ¹Π_g	34515.25	618.95 Z	3.00		0.27524	0.00168		2.2E-7		1.9887	A → X R	34434.30 Z
A ¹Π_g	↳missing citation; Verma and Broida, 1970; Malicet, Brion, et al., 1973; missing citation
b ²Π_g2	28329.6	644.66 Z	3.213 35		0.2805	0.00178		2.0E-7		1.970	b → a 32 V	9574.8 Z
b ²Π_g2	↳Mrozowski and Santaram, 1967; Brion and Malicet, 1975; missing citation; Carroll and Nulty, 1976
b ²Π_g1	28197.0	644.66 Z	3.213 35		0.2805	0.00178		2.0E-7		1.970	b → a 32 V	9442.2 Z
b ²Π_g1	↳Mrozowski and Santaram, 1967; Brion and Malicet, 1975; missing citation; Carroll and Nulty, 1976
b ²Π_g0	28068.9	644.66 Z	3.213 35		0.2805	0.00178		2.0E-7		1.970	b → a 32 V	9314.1 Z
b ²Π_g0	↳Mrozowski and Santaram, 1967; Brion and Malicet, 1975; missing citation; Carroll and Nulty, 1976
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
b' ³Σ_u^-	28503.4 36	604.4₈ Z	2.2		0.2584 37	0.0014		1.7E-7		2.052	b' → X R	28415.4 Z
b' ³Σ_u^-	↳Mrozowski and Santaram, 1967; missing citation
a ³Σ⁺	18794.5	565.1₇ H	2.7₅		B₁=0.2503₃ 38			D₁=3.3E-7		r₁=2.085₃	(a-X)	18686.7 39
X ¹Σ_g⁺	0	780.77 Z	2.83₅ 40	-0.00462	0.30362 22	0.00149 41	-2.7E-6	1.88E-7		1.8934

Notes

Core configuration as suggested by Bulgin, Dyke, et al., 1976 on the basis of ab initio calculations; Carroll and Mitchell Carroll and Mitchell, 1975 proposed... 4σ_u² 5σ_g 2π_u³ 2π_g.

Carrol and Mitchel's Rydberg series G_n, H_n, P_n, R_n converging to A ²Σ_g⁺(v=0):

v=87179 - R/(n-0.062-0.633/n*²)², n=4(R₄),5...21.

v=87179 - R/(n-0.155-0.179/n*²)², n=4(P₄),5...14.

v=87179 - R/(n-1.468-0.475/n*²)², n=4(H),5(H₅),6...28.

v=87179 - R/(n-1.660-0.252/n*²)², n=4(G),5(N),6(G₆),7...12.

Carrol and Mitchel's Rydberg series E_n, K_n, M_n, L_n converging to X₂ ²Π_1/2(v=1):

v~85895 - R/(n+0.04)², n=3(L),4. Fragments of series with v'=0 (V =85229) and with v'>1.

v~85895 - R/(n+0.03)², n=3(M),4(M₄),5(S). Fragments of series with v'=0 (V =85229) and with v'>1.

v~85895 - R/(n+0.12)², n=3(K),4...10. Fragments of series with v'=0 (V =85229) and with v'>1.

v~85895 - R/(n+1.93)², n=4(E),5(E₅),6. Fragments of series with v'=0 (V =85229) and with v'>1.

Observed to v'=2.

Diffuse bands.

Observed to v'=4.

Assigned as 0-0 band by Creutzberg, 1966; reassigned as 1-0 band by Carroll and Mitchell, 1975 [third member of the M_n(v'=1) Rydberg series].

Broad diffuse bands.

0-0 and 1-1 bands only.

Broad band.

Only v'=1 and 3 (diffuse) observed.

0-0 band obscured by H₅← X 0-0.

Very broad band.

RKR potential functions Singh and Rai, 1966, Rao and Lakshman, 1970.

Following Carroll and Mitchell, 1975 the v' numbering of Creutzberg, 1966 has been increased by one unit.

All lines of this system are diffuse; the diffuseness is largest for v'=3 and 4 such that the rotational structure can no longer be recognized. The broadening is independent of J; the state causing the predissociation is probably ¹Π_u.

Very intense diffuse band, width ~80 cm^-1.

Franck-Condon factors Rao and Lakshman, 1970.

The assignment of v'=0 to the lowest observed level is arbitrary.

ΔG(3/2) = 352.71.

B₁ = 0.2209, B₂ = 0.217₁.

Carroll and Nulty, 1976; slightly different constants in missing citation.

Perturbations by C ¹Σ_u⁺. The observation of extra lines enables the relative position of singlet and triplet levels to be determined Carroll and Nulty, 1976; very similar results have been obtained by Brion, Malicet, et al., 1976, missing citation.

Franck-Condon factors Brion and Malicet, 1976.

Constants from Creutzberg, 1966, but see missing citation whose deperturbation of the C state levels (see 34) leads to T_e = 46945.5₇, ω_e = 472.81, ω_ex_e = 2.24₆, ω_ey_e = +0.00412₂.

Strong vibrational perturbations for v=1,2,3,5 Herzberg, 1932 and many rotational perturbations Marais, 1946, Marais and Verleger, 1950, Naude and Verleger, 1950, Creutzberg, 1966, Brion, Malicet, et al., 1976, 2 due to interaction with levels of c ³Π_u see missing citation. Breaking off in emission (predissociation) above J=58 of v=10 and J=34 of v=11; the corresponding dissociation limit is ⁴S + ²D at 51959 ± 25 cm^-1. A second predissociation indicated by diffuseness in absorption begins at v=17 and reaches a maximum for low J values of v=19 Creutzberg, 1966.

ω_ey_e < 0.001 cm^-1 Carroll and Nulty, 1976; slightly different constants in missing citation.

Recalculated; Brion, Malicet, et al., 1974 give 28507.74 which probably refers to data obtained from band heads rather than band origins.

Spin splitting constants λ = +3.20, γ = -0.001.

Spin splitting constants λ₁= -3.2₁, γ₁= -0.003 Brion and Malicet, 1976.

Not observed; indirectly derived Carroll and Nulty, 1976 from perturbations in c ³Π_u; see 31.

missing citation; slightly different constants in Marais and Verleger, 1950 and Creutzberg, 1966.

Constants recalculated from the data of Herzberg, 1932, Douglas and Rao, 1958, Creutzberg, 1966, Dixit, 1968. Higher B_v values not included in the reevaluation may be found in Herzberg, 1932, Marais and Verleger, 1950.

From the predissociation limit in C ¹Σ_u+ which according to Herzberg, 1932 is equal to the dissociation limit ⁴S+²D. The latest thermochemical (mass-spectrometric) value is 5.04 eV Kordis and Gingerich, 1973 eliminating the possibility that the predissociation limit corresponds to ²D+²D as suggested by Vaidyan and Santaram, 1971.

From the photoelectron spectrum Bulgin, Dyke, et al., 1976 which shows partially resolved peaks at 10.53 and 10.55 eV corresponding to X₁ ²Π_3/2 and X₂ ²Π_1/2, respectively. Subtraction of the estimated doublet splitting in the X ²Π ground state [~ 260 cm^-1, see ref. 6 of P₂⁺] from the Rydberg series limit at 85229 cm^-1 Carroll and Mitchell, 1975 gives l0.53₅ eV.

References

Go To: Top, Constants of diatomic molecules, Notes

Carroll and Mitchell, 1975
Carroll, P.K.; Mitchell, P.I., The absorption spectrum of diatomic phosphorus between 1370 and 600 A, Proc. Roy. Soc. London A, 1975, 342, 93. [all data]

Creutzberg, 1966
Creutzberg, F., The absorption spectrum of the P₂ molecule in the vacuum ultraviolet, Can. J. Phys., 1966, 44, 1583. [all data]

Dressler, 1955
Dressler, K., Ultraviolett- und Schumannspektren der neutralen und ionisierten Molekule PO, PS, NS, P₂, Helv. Phys. Acta, 1955, 28, 563. [all data]

Malicet, Brion, et al., 1973
Malicet, J.; Brion, J.; Guenebaut, H., Analyse de quatre bandes d'une nouvelle transition ¹Π-¹Π du radical P₂, C.R. Acad. Sci. Paris, Ser. C, 1973, 276, 991. [all data]

Brion, da Paz, et al., 1971
Brion, J.; da Paz, M.; Mongin, J.; Guenebaut, H., Analyse rotationnelle de quatre nouvelles bandes d'un systeme electronique visible du radical P₂, C.R. Acad. Sci. Paris, Ser. B, 1971, 272, 999-1002. [all data]

Carroll and Nulty, 1976
Carroll, P.K.; Nulty, A.T., Rotational analysis of the visible system of P₂ and the location of the triplet states, J. Phys. B:, 1976, 9, 427. [all data]

Marais and Verleger, 1950
Marais, E.J.; Verleger, H., The rotational structure of the ultraviolet band system of the P₂ molecule, Phys. Rev., 1950, 80, 429. [all data]

Verma and Broida, 1970
Verma, R.D.; Broida, H.P., Spectral study of the phosphorus glow, Can. J. Phys., 1970, 48, 2991. [all data]

Mrozowski and Santaram, 1967
Mrozowski, S.; Santaram, C., Electronic spectra of P₂, As₂, and Sb₂ molecules, J. Opt. Soc. Am., 1967, 57, 522. [all data]

Brion and Malicet, 1975
Brion, J.; Malicet, J., Nouvelle transition du radical P₂ analogue au premier systeme positif de l'azote, J. Phys. B:, 1975, 8, 164. [all data]

Bulgin, Dyke, et al., 1976
Bulgin, D.K.; Dyke, J.M.; Morris, A., HeI photoelectron spectrum of the P₂(X¹Σ⁺₎ molecule, J. Chem. Soc. Faraday Trans. 2, 1976, 72, 2225. [all data]

Singh and Rai, 1966
Singh, R.B.; Rai, D.K., Potential curves for some diatomic molecules: P₂, PN, SiN, NBr, BaO, BeF, SiF & SnF, Indian J. Pure Appl. Phys., 1966, 4, 102. [all data]

Rao and Lakshman, 1970
Rao, T.V.R.; Lakshman, S.V.J., Potential energy curves, r-centroids & Franck-Condon factors for the bands of P₂ molecule, Indian J. Pure Appl. Phys., 1970, 8, 617. [all data]

Brion, Malicet, et al., 1976
Brion, J.; Malicet, J.; France, M.; Lafore, M., Peturbations dans les etats C¹Σ_u⁺ et c³Π_u du radical P₂, C.R. Acad. Sci. Paris, Ser. C, 1976, 283, 171. [all data]

Brion and Malicet, 1976
Brion, J.; Malicet, J., Spectre d'emission du radical P₂: transitions c³Π_u-b³Π_g et b³Π_g-a³Σ_u⁺, J. Phys. B:, 1976, 9, 2097. [all data]

Herzberg, 1932
Herzberg, G., Bandenspektrum, pradissoziation und struktur des P₂-molekuls, Ann. Phys. (Leipzig), 1932, 15, 677. [all data]

Marais, 1946
Marais, E.J., Perturbations in the ultraviolet band spectrum of P₂, Phys. Rev., 1946, 70, 499. [all data]

Naude and Verleger, 1950
Naude, S.M.; Verleger, H., The perturbations in the ultraviolet band spectrum of the phosphorus molecule P₂, Phys. Rev., 1950, 80, 432. [all data]

Brion, Malicet, et al., 1976, 2
Brion, J.; Malicet, J.; Guenebaut, H., Spectre d'emission du radical P₂: etude des transitions C¹Σ_u⁺-X¹Σ_g⁺, A¹Π_g-X¹Σ_g⁺ et B¹Π_u-A¹Π_g, Can. J. Phys., 1976, 54, 362. [all data]

Brion, Malicet, et al., 1974
Brion, J.; Malicet, J.; Guenebaut, H., Spectre d'emission du radical P₂: etude de la transition b'³Σ_u^- - X¹Σ_g⁺, Can. J. Phys., 1974, 52, 2143-2149. [all data]

Douglas and Rao, 1958
Douglas, A.E.; Rao, K.S., A new band system of the P₂ molecule analogous to the Lyman-Birge-Hopfield bands of N₂, Can. J. Phys., 1958, 36, 565. [all data]

Dixit, 1968
Dixit, M.N., Rotational analysis of some bands of C¹Σ_u⁺-X¹Σ_g⁺ system of P₂ molecule involving low v', v" values, Proc. Indian Acad. Sci. Sect. A, 1968, 66, 325. [all data]

Kordis and Gingerich, 1973
Kordis, J.; Gingerich, K.A., Mass spectroscopic investigation of the equilibrium dissociation of gaseous Sb₂, Sb₃, Sb₄, SbP, SbP₃, and P₂, J. Chem. Phys., 1973, 58, 5141. [all data]

Vaidyan and Santaram, 1971
Vaidyan, V.K.; Santaram, C., Dissociation energy & potential energy curves of P₂, Indian J. Pure Appl. Phys., 1971, 9, 1022. [all data]

Notes

Go To: Top, Constants of diatomic molecules, References

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
Customer support for NIST Standard Reference Data products.