Spectroscopic Constants of Diatomic Molecules

This table lists the leading spectroscopic constants and equi-librium internuclear distance re in the ground electronic state for selected diatomic molecules . The constants are those describing the vibrational and rotational energy through the expressions: where

Bv = Be – αe(v+1/2) + …

Dv = De + …

Evib /hc = ωe(v + 1/2) – ωexe(v + 1/2)2 + …Erot /hc = BvJ(J + 1) – Dv[J(J + 1)]2 + …

In such cases it has been assumed that Y10 = ωe , Y01 = Be , etc ., although in the highest approximations these identities are not precisely correct . Some of the values of re in the table have been corrected for breakdown of the Born-Oppenheimer approxima-tion, which can affect the last decimal place . Because of differences in the method of data analysis and limitations in the model, care should be taken in comparing re values for different molecules to a precision beyond 0 .001 Å .

Molecules are listed in alphabetical order by formula as writ-ten in the most common form . In most cases this form places the more electropositive element first, but there are exceptions such as OH, NH, CH, etc .

* Indicates a value for the interval between v = 0 and v = 1 states instead of a value of ωe .

Here v and J are the vibrational and rotational quantum numbers, respectively, h is Planck’s constant, and c is the speed of light . In this customary formulation the constants ωe, Be , etc . have dimensions of inverse length; in this table they are given in units of cm–1 .

Users should note that higher order terms in the above energy expressions are required for very precise calculations; constants for many of these terms can be found in the references . Also, if the ground electronic state is not 1Σ, additional terms are needed to account for the interaction between electronic and pure rotational angular momentum . For some molecules in the table the data have been analyzed in terms of the Dunham series expansion:

molecule107

Ag79Br107

Ag35Cl107

Ag19F107

Ag1H107

Ag2H107

Ag127I107

Ag16O27

Al227

Al79Br27

Al35Cl27

Al19F27

Al1H27

Al2H27

Al127I27

Al16O27

Al32S75

As275

As1H75

As2H75

As14N75

As16O197

Au2197

Au1H197

Au2H11B21179BBr1135BCl1119BF111BH112BH1114BN1116BO

references

1 . Huber, K . P ., and Herzberg, G ., Molecular Spectra and Molecular

Structure IV. Constants of Diatomic Molecules, Van Nostrand Reinhold, New York, 1979 .

2 . Lovas, F . J ., and Tiemann, E ., J. Phys. Chem. Ref. Data, 3, 609, 1974 . 3 . Landolt-Börnstein, Numerical Data and Functional Relationships in

Science and Technology, New Series, II/6 (1974), II/14a (1982), II/14b (1983), II/19a (1992), II/19d-1 (1995), Molecular Constants, Springer-Verlag, Heidelberg .Becm–1

0 .0648330 .122983880 .26570206 .4493 .2572

0 .044868210 .30200 .171270 .159197130 .243930120 .55247986 .39073 .3186

0 .117699850 .64140 .27990 .101797 .30673 .66880 .545510 .484820 .0280137 .24013 .64151 .2120 .48940 .6842821 .51695012 .0216 .541 .6661 .7820

αe

cm–1

0 .00023610 .000595410 .00192060 .2010 .07220 .00014140 .00250 .0008

0 .000860450 .001611130 .00498410 .18580 .0697

0 .000558590 .00580 .00180 .0003330 .21170 .0033660 .0032990 .00007230 .21360 .076140 .0140 .00350 .0068120 .0190560 .4120 .170 .0250 .0166

De

10–6cm–10 .01750 .063050 .28434485 .90 .008470 .450 .112850 .25031 .0464356 .5971 .080 .22327900 .530 .490 .0025027970 .91 .001 .847 .10512424008 .16 .32

reÅ

2 .393112 .280791 .983181 .6181 .61802 .544632 .0032 .7012 .294812 .130111 .654371 .64781 .64632 .537101 .61792 .0292 .10261 .523151 .53061 .61841 .62362 .47191 .52391 .52381 .5901 .8881 .715281 .262671 .23241 .23241 .2811 .2045

E/hc = Σlm Ylm(v+1/2)lJm(J+1)m

state 1+Σ1+Σ1+Σ1 +Σ1 +Σ1 +Σ2

Π1/23Πu1 +Σ1 +Σ1 +Σ1 +Σ1 +Σ1 +Σ2 +Σ2 +Σ1

Σg+3 -Σ3 -Σ1 +Σ2

Π1/21

Σ g+1 +Σ1 +Σ3

Σ g-1 +Σ1 +Σ1 +Σ1 +Σ1 +Σ3Π2 +Σ

ωecm–1249 .57343 .49513 .451759 .91250 .70206 .50490 .2285 .8378 .0481 .30802 .31682 .561211 .95316 .1979 .23617 .1429 .552130*1484*1068 .54967 .08190 .92305 .011634 .981051 .3684 .31840 .291402 .12366 .91703 .31514 .61885 .69

ωexecm–1 0 .631 .172 .5934 .0617 .170 .463 .10 .91 .281 .954 .7729 .0915 .141 .06 .973 .331 .12

5 .414 .850 .4243 .1221 .659 .353 .525 .4911 .849 .402812 .311 .81

9-103

9-104

spectroscopic Constants of diatomic molecules

molecule11B32state 2BaSΣ +138

79Br2Σ +138

Ba35Cl2Σ +138

Ba19F2Σ +138

Ba12BaHΣ +138

22BaHΣ +138

1272OIΣ +138

Ba161Σ +138

Ba32S1Σ +9

Be192BeFΣ +9

1H2Σ +9

Be22BeHΣ +9

16O1Σ +9

Be321BiSΣ +209

1

Σ209Bi21

g+3BiHΣ -2092

H3Σ -79

Br1

Σ79

Br235BrClΣ g+1 +79

19F1Σ +79

Br162

COΠ121

Σ3/212C235 g+2

CClΠ1219F2

Π1/212C1H2

Π1/212C22

CHΠ1/212142CNΣ +1/212161COΣ +1231P2Σ +12C32S1Σ +12C80Se1Σ +40

Ca352CaClΣ +40

192CaFΣ +40

1H2Σ +40

Ca2H2Σ +40

Ca127I2Σ +40

Ca161CaOΣ +40

32S1Σ +114

Cd12CdHΣ +114

2H2Σ +35

Cl1

Σ35

Cl219ClFΣ g+1 +35

162

CrOΠ52

1H6Σ +3/252

Cr2H6Σ +52

Cr16O5Π133

Cs1

Σ133

Cs2791CsBrΣ g+ +133

35Cl1Σ +133

Cs19F1Σ+133

Cs11CsHΣ+133

2H1Σ+133

Cs127I1Σ+133

Cs162CuOΣ+63

1

Σ63

Cu279BrΣg+1+65

Cu35Cl1Σ+63

Cu19F1Σ+63

Cu11CuHΣ+63

2H

1Σ

+ωcme–1

ω1180 .17cmex–1e193 .776 .31 279 .920 .41468 .90 .821168 .311 .79829 .7714 .50152 .147 .32669 .760 .27379 .422 .031247 .360 .882060 .789 .121530 .3236 .311487 .3220 .71997 .9411 .83172 .716 .141635 .730 .341173 .3231 .6325 .3216 .1444 .281 .08670 .751 .847794 .051854 .716 .8866 .72*13 .341308 .16 .22858 .511 .102099 .863 .02068 .5934 .022169 .8113 .091239 .6713 .291285 .156 .861035 .366 .50367 .534 .86581 .11 .311298 .342 .74910*19 .10238 .70732 .030 .63462 .234 .831337 .1*1 .78

559 .7786 .152 .68853 .86 .161581*5 .51182*32898 .442 .026 .8149 .660 .08214 .170 .37352 .560 .73891 .01 .62619 .1*12 .9119 .18357 .5*0 .25264 .55314 .81 .02415 .290 .96622 .71 .581941 .263 .951384 .14

37 .5118 .97

Bcme–10 .79490 .04150820 .083967170 .21593 .382851 .7071

0 .026805870 .31261400 .103311 .488910 .31645 .68721 .65100 .790590 .0227815 .1372 .5920 .0821070 .1524700 .355840 .4295981 .81980 .69361 .417214 .4577 .806

1 .89978301 .931280750 .79860 .82004340 .57500 .15223020 .3394 .27662 .17690 .06932630 .4444410 .17667575 .3232 .7040 .24400 .5164790 .623456 .2203 .140 .52310 .0127

0 .036069250 .072091490 .184369692 .70991 .354

0 .023627360 .2230730 .108740 .101926250 .176288020 .37940297 .94414 .0381

αcme

–10 .00610 .00012190 .000334290 .00120 .065990 .023630 .000066340 .00139210 .00031880 .01760 .30300 .12250 .01900 .006640 .0000550 .1480 .054

0 .00031870 .0007700 .002610 .0036390 .01770 .006720 .01840 .5340 .208

0 .01737170 .017503900 .005970 .00591820 .003790 .00079900 .00260 .09700 .035

0 .00026340 .0032820 .0008270

0 .00150 .0043580 .00580 .1790 .00700 .00002640 .000124010 .000337560 .00117560 .05790 .000068260 .0013030 .0006140 .000452140 .000996470 .00322980 .25630 .0917

D10e

–6r1 .40cm–1Å

e0 .007621 .60920 .030222 .844490 .1752 .68276112 .672 .16328 .772 .231750 .003332 .23040 .27243 .084760 .03061 .939698 .282 .50741022 .11 .3610313 .81 .34268 .201 .34192 .001 .33090 .001501 .74151832 .659650 .61 .8050 .020921 .8040 .071832 .28110 .4012 .136070 .5231 .758946 .921 .7171 .91 .24256 .51 .645014501 .27184201 .11996 .40341 .11906 .12161 .171811 .331 .128231 .3361 .5620 .711 .534820 .10291 .676090 .452 .43676183 .71 .96747 .92 .00250 .02342 .0020 .65412 .828590 .10321 .82213142 .31775761 .7810 .1861 .7750 .881 .9881 .331 .628313471 .5696388 .81 .6561 .6640 .004641 .6150 .008384 .470 .032683 .072250 .201682 .906271132 .3453520

2 .49380 .003712 .5050 .3483 .315190 .07162 .30070 .042742 .21970 .127062 .173440 .5632 .051185201 .74493136 .2

1 .462631 .4626

spectroscopic Constants of diatomic molecules

9-105

molecule63

Cu127state 1CuIΣ+63

16O2

Π63

Cu32S2

Π3/219F1

Σ3/256

Fe216O∆g+569

Ga81Br1Σ+69

Ga351GaClΣ+69

19F1Σ+69

Ga11GaHΣ+69

2H1Σ+69

Ga1271GaIΣ+69

16O2Σ74

Ge79Br2

Π74

Ge35Cl2

Π1/272

Ge12

GeHΠ1/272

22

GeHΠ1/274

16O1Σ+1/274

Ge32S1Σ+74

Ge80Se1Σ+74

Ge1301HTeΣ+11

Σ2H2g+1

Σ3H2g+1

Σ1H2811HBrΣg++281Br1Σ+1H351HClΣ+2351HClΣ+1191HFΣ+219F1Σ+1H127I1Σ+202

Hg1H2Σ+202

Hg22IHΣ+127

1

Σ127I279

1IBrΣg++12735

Cl1Σ+127I19

1IFΣ+12716

O2

Π115

In811InBrΣ+3/2115

35Cl1Σ+115

In19F1Σ+115

In1H1Σ+115

In21Σ+1KInH115

127IΣ+391

Σ39K279BrΣg+1+39K351KClΣ+39191KΣ+1KHF391Σ+392H1Σ+39K127I1Σ+139

2LiLa16OΣ+71

Σ7Li2791LiBrΣg++7351LiClΣ+7191LiFΣ+71H1Σ+7Li2H1Σ+7Li1271LiIΣ+7162MgOΠ24

2

1

Σg+

ωcme–1ω264 .5cmex–1e640 .170 .60 415 .04 .43916 .641 .75965*11 .24263 .0365 .670 .81622 .21 .251604 .523 .228 .77216 .38767 .50 .472956 .24407 .60 .71833 .771 .361320 .0937986 .4919575 .84 .47408 .71 .80323 .91 .364401 .210 .753115 .50121 .342546 .561 .822648 .9741 .231884 .7545 .222990 .9522 .722145 .1652 .824138 .3227 .182998 .1989 .882309 .0145 .761203 .24*39 .64

896 .12*214 .50268 .640 .61384 .290 .81610 .241 .50681 .53 .12221 .04 .3317 .390 .65535 .41 .031476 .02 .61048 .225 .61177 .0812 .492 .020 .342130 .282810 .80426 .261 .30983 .62 .4570714 .3186 .537 .7812 .80 .57351 .432 .22563 .22 .61642 .953 .5910 .574 .471405 .658 .211054 .8023 .20496 .8512 .94814 .622 .8551 .12

7 .781 .64

Bcme–1

0 .073287420 .444540 .18910 .890190 .6500 .0818390 .14990460 .35951616 .1373 .083

0 .05693590 .4271

6 .7263 .415

0 .48569810 .186565760 .096340510 .0653382160 .85330 .44420 .3358 .464884 .24559610 .593425 .44879620 .955711 .01026 .42636505 .38882 .7390 .037370 .05683250 .11415870 .27971110 .340260 .054894680 .10905830 .26232414 .9952 .523

0 .036867020 .0567430 .081221090 .12863480 .279937413 .4164001 .754

0 .060874730 .352520010 .672640 .5553990 .70652251 .34525837 .513734 .233100 .44317661 .2128300 .09287

αcme

–1

0 .000283900 .004560 .0138470 .00032070 .00079360 .00286420 .1810 .06

0 .0001897

0 .1920 .070

0 .00307870 .000749100 .000289040 .000172463 .0621 .07860 .58870 .233280 .0840 .307180 .1132920 .7980 .30170 .1689

0 .0001140 .00019690 .00053540 .00187380 .002700 .000186720 .00051770 .00187980 .1430 .051

0 .000104110 .0001650 .000404810 .00078990 .002334920 .0853130 .0318

0 .000267760 .001423650 .007040 .0056440 .00801020 .02028870 .216650 .091550 .00408620 .0178990 .00378

D10e

–6cm–1r0 .02244Å

e0 .852 .338320 .181 .72443 .32 .0510 .721 .411930 .0321 .4440 .10082 .352480 .502 .201693421 .7743784

1 .6630 .0157701 .6630 .37

2 .574641 .744

32683 .21 .58800 .47091 .58740 .078831 .624640 .022072 .012090 .0122 .13463471002 .34017114100 .741440 .74152345 .80 .7414288 .321 .41444531 .941 .41451401 .2745521511 .274585940 .91681206 .90 .91694395 .31 .60916911 .76620 .00431 .7570 .01022 .6660 .04032 .468990 .23562 .320880 .361 .909760 .013501 .86760 .05152 .543150 .2522 .401172231 .9854058

1 .83800 .006391 .8370 .08632 .753640 .044623 .90510 .10872 .820780 .48292 .66665163 .552 .1714650

2 .2430 .025932 .2400 .26263 .047849 .871 .825912 .1592 .67293 .4092 .1704311 .7452 .020678621 .563862761 .594901 .41041 .59410 .10792 .391921 .22

1 .688223 .891

9-106

spectroscopic Constants of diatomic molecules

molecule24

Mg35state 2MgClΣ+24

192HFΣ+24

Mg12Σ+24

Mg22MgHΣ+24

16O1Σ+55

Mn1H7Σ55

Mn2H7Σ14N1

Σ14N2793NBrΣg+-14353NClΣ-1419F3Σ-14N13NHΣ-1423NHΣ-14162

NOΠ1432S2

Π1/223

Na1

Σ1/223

Na279BrΣg+1+23

Na35Cl1Σ+23

Na19F1Σ+23

Na11NaHΣ+23

2H1Σ+23

Na1271NaOIΣ+23

162Π93

Nb164NiOΣ-58

1H2

∆58

Ni2H2

∆5/216O3Σ5/216O212

OHΠg-162H2

Π3/231P1

Σ3/231P2353PClΣg+-3119F3Σ-31P1H3Σ-31P23PHΣ-31141PNΣ+31162

PbOΠ208

1/2208

Pb279Br2

Π208

Pb352

PbClΠ1/2208

19F2

Π1/2208

Pb12

PbHΠ1/2208

16O1Σ+1/2208

Pb32S1Σ+208

Pb80Se1Σ+208

Pb1301PtTeΣ+195

121PtCΣ+195

1H2

∆195

Pt2H2

∆5/285

Rb79Br1Σ5/2+85

Rb351RbClΣ+85

19F1Σ+85

Rb11RbH85

127IΣ+1Σ+85

Rb162SOΣ+323Σ32S219g-2

SFΠ321H2

Π3/232S22

SHΠ3/23216O3Σ-3/2121

Sb35Cl

3Σ

-ωcme–1ω462 .12*cmex–1e711 .69*2 .1 1495 .204 .91077 .931 .89784 .7816 .11548 .05 .26110328 .82358 .5713 .9691 .7514 .32827 .964 .721141 .375 .303282 .38 .99239878 .41904 .20421218 .714 .07159 .137 .283020 .723661 .5535 .662 .051172 .23 .57826 .1*19 .72258492 .31 .1989 .01926 .63 .81390 .1381580 .19193737 .7611 .982720 .2484 .88780 .7744 .05551 .382 .84846 .752 .232365 .24 .491699 .244 .51337 .2423 .01233 .346 .98110 .56 .56207 .50 .35303 .90 .50502 .730 .881564 .12 .28720 .9629 .75429 .173 .52277 .61 .26212 .00 .511051 .130 .432294 .68*4 .861644 .3*46169 .46232280 .463760 .92936 .91 .9138 .5114 .21388 .4*0 .33725 .652 .842711 .6188559 .91149 .231374 .7

5 .60 .6

Bcme–1

0 .24561540 .519225 .82573 .0306

0 .574704365 .68412 .89571 .998240 .4440 .6497701 .205716 .69938 .79131 .671950 .7696020 .1547070 .15125330 .21806310 .43690114 .90336342 .5570890 .11780560 .4246300 .43217 .7003 .9921 .4456318 .91110 .0210 .303620 .25287480 .56658 .53714 .40810 .78648540 .7337

0 .228754 .971

0 .307303730 .116323070 .050599530 .031307740 .530447 .19633 .640

0 .047527980 .08764040 .21066403 .020

0 .032832930 .2464810 .29550 .5521749 .59954 .951300 .7208171

αcme

–1

0 .00162040 .004700 .18590 .062890 .005323770 .15700 .0510 .0173180 .00400 .0064140 .014920 .64900 .25310 .01710 .00640 .0087360 .00094100 .00162480 .00455800 .13709190 .0516000 .00064780 .0045060 .00210 .230 .0920 .01590 .72420 .2760 .001490 .00151190 .004560 .25140 .09280 .00553640 .0055

0 .0014730 .144

0 .001909770 .000435100 .000129930 .000067430 .0032730 .19960 .071

0 .000185960 .00045370 .00152280 .072

0 .000109460 .0021740 .0015700 .27850 .103080 .005737

D10e

–6cm–1r0 .2723Å

e1 .0802 .196393441 .7500921 .72971 .23281 .7302303 .91 .7483879 .51 .73115 .761 .73101 .097691 .5981 .795 .391 .610711709 .71 .3170490 .41 .03620 .51 .03611 .21 .150770 .5811 .49400 .15543 .07890 .31202 .502041 .1632 .36080343 .401 .9259593 .461 .886540 .09731 .886541 .26382 .711450 .222 .051554811 .6911301 .4764 .8391 .46519381 .20752537 .40 .969660 .1880 .96980 .21241 .89342 .014614361 .589381161 .421401 .0911 .42201 .3

1 .490871 .4759

0 .1832012 .05750 .21381 .8390 .034181 .921810 .00702 .286780 .00272 .402180 .5462 .594922611 .676766

1 .528520 .014961 .5240 .049472 .944740 .26842 .786731232 .270330 .007382 .3670 .3973 .176880 .192 .254201 .8892480 .61 .600581301 .340661 .1341 .340491 .48109

spectroscopic Constants of diatomic molecules

9-107

molecule121

Sb19state 3SbFΣ-121

1H3Σ-121

Sb2H3Σ-121

Sb14N1Σ+121

Sb162

ScOΠ45

191SeFΣ+1/280

3Σ80

Se21Hg-2

Π80

Se22

SeHΠ3/280

16O3Σ-3/228Si3Σ28Si235g-2

SiClΠ28192

SiFΠ1/2281H2

Π1/228Si22

SiHΠ1/228142SiNΣ+1/228161SiOΣ+2832S1Σ+28Si801SnSeΣ+120

79Br2

Π120

Sn352

SnClΠ1/2118

19F2

Π1/2120

Sn1H2

Π1/2120

Sn2H2

Π1/2120

Sn1272

SnIΠ1/2120

161SnOΣ+1/2120

32S1Σ+120

Sn80Se1Σ+120

Sn130Te1Σ+88

Sr792SrBrΣ+88

35Cl2Σ+88

Sr192SrHFΣ+88

12Σ+88

Sr22SrHΣ+88

127I2Σ+88

Sr16O1Σ+181

Ta16O2

∆130

Te3Σ3/2130

Te21Hg-2

130

Te16ThO0Π+3/2232

16O1Σ+48Ti163TlO∆205

81Br1Σ1+205

Tl351TlClΣ+205

19F1Σ+205

Tl1H1Σ+205

Tl2H1Σ+205

Tl1271VIΣ+51164YOΣ-8935Cl1Σ89Y191YFΣ+8916O2Σ+174

Yb12YbHΣ+174

2H2Σ+64

Zn352ZnClΣ64

19F2Σ64

Zn12ZnHΣ+64

2H2Σ+64

Zn127I2Σ90

Zr16O

1Σ

+ωcme–1ωcmex–1e605 .0

2 .6

942 .08165 .6735 .64 .2385 .303 .82400*0 .96

1708*914 .69510 .984 .52535 .602 .02857 .192 .172041 .804 .731469 .3235 .511151 .418 .231241 .546 .47749 .645 .97580 .02 .58247 .21 .78351 .10 .6577 .61 .062 .69

1188 .0*199 .0822 .130 .6487 .263 .72331 .21 .36259 .50 .74216 .600 .50302 .30 .52502 .40 .951206 .22 .384117 .0173 .778 .6653 .50 .351028 .693 .96247 .073 .510 .51797 .11895 .774 .001009 .022 .39192 .104 .50284 .710 .39476 .860 .861390 .72 .24987 .722 .7150*12 .041011 .3380 .74 .86631 .291 .3861 .02 .501249 .542 .9886 .621 .06390 .510 .576281 .61607 .63 .5107255 .14223 .428969 .8

0 .64 .9

Bcme–10 .27925 .6842 .87820 .35800 .39500 .089928 .023 .940 .46550 .23900 .25610 .58127 .49963 .88400 .73110 .72675210 .303527880 .19201170 .11170 .27275 .314882 .69500 .355719980 .136861390 .06499780 .042479170 .05418470 .25053463 .67511 .86090 .03670970 .337980 .402840 .0396815 .560 .35540 .3326440 .535410 .04238990 .091397020 .223150144 .8062 .419

0 .02716760 .548250 .11600 .290420 .38813 .99312 .01162

6 .67943 .3500 .42263

αcme

–10 .0020

0 .00220 .002660 .0002880 .230 .003230 .00140 .00160 .004940 .21900 .07810 .005650 .00503790 .001473080 .00077670 .00040 .00140 .0490 .002144320 .000505630 .00017050 .000095430 .00018270 .00155130 .08140 .02920 .00010600 .002190 .001820 .0001060 .002370 .0013020 .003010 .00012760 .000397840 .001503800 .1540 .057

0 .00006640 .003520 .00030 .001630 .00180 .09570 .03425

0 .2500

0 .0023

D10e

–6r0 .23cm–1Åe2401 .918451 .7231 .71940 .2701 .8260 .0241 .7883302 .1661 .480 .51 .480 .211 .6480 .252 .2461 .072 .0583971 .6011105 .41 .52011 .21 .51990 .99231 .5720 .2011 .509750 .0842

1 .929262 .058320 .262 .361207 .51 .94453 .41 .781461 .77700 .266380 .04241 .832510 .0112 .208980 .00552 .325570 .013562 .522802 .735220 .24981352 .0753734 .72 .14560 .006552 .14490 .362 .943640 .24501 .919830 .00441 .687462 .55740 .271 .740 .18331 .8250 .6031 .840320 .00831 .62020 .03771 .618170 .19552 .484832542 .08439601 .8700 .00361 .8690 .62 .813610 .091 .58930 .2372 .410 .321 .9257161 .81 .79041 .60

2 .05262 .0516

4661241 .59491 .60540 .319

1 .7116