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X-ray photoelectron spectra of inorganic molecules—XV[1,2]. Complexes of thallium(III) chloride
Notes
Solid State Chemistry Department G. BLASSE State University G . P . M . VAN DEN HEUVEL Sorbonnelaan 4 Utrecht The Netherlands REFERENCES ~. G. Blasse, Z. Anorg. Allg. Chem. 331, 44 (1964). 2. J. M. R6au, C. Fouassier and P. Hagenmuller, Bull. Soc. Chim. (Fr.) 3873 (1967).
549
3. G. Blasse and G. P. M. van den Heuvel, Phys. Star. Sol. (a) 19, 111 (1973). 4. F. A. Krtger, Some Aspects of the Luminescence of Solids, Elsevier, Amsterdam (1948). 5. J. H. G. Bode, H. R. Kuijt, M. A. J. Th. Lahey and G Blasse. J. Solid State Chem. 8, 114 (1973). 6. G. Blasse, J. lnorg. Nucl. Chem. 37, 97 (1975). 7. L. Pauling, The Nature of the Chemical Bond, 3rd Edn. Cornell University Press, New York (1960). 8. G. Blasse and A. Bril, J. Solid State Chem. 2, 291 ! 1970}. 9. Yu. S. Leonov, Opt. Spectroscopy 9, 145 (19601.
f inorz nut! (?hem., 1977, Vol 39. pp. s49-550. Pergamon Press. Printed in Great Britain
X-Ray photoelectron spectra of inorganic molecules--XV[l, 2]. Complexes of thallium(lII) chloride (Received 28 June 1976) Our previous isolation and characterization of a variety of complexes of thallium(Ill) chloride[3,4] has led to the present investigation of the X-ray photoelectron spectra (XPS) of several such derivatives. This study was initiated to explore the possibility that in ionic complexes such as [TICl2(terpy)]+[TICl4] and [TtCl2(phen)2HTIC14(phen)] , where terpy = 2,2',2"terpyridyl[4, 5] and phen = 1 : 10-phenanthroline[3], the cationic and anionic thallium species could be distinguished by differences in their TI 4f binding energies. The appropriate XPS data for the complexes considered in the present investigation are summarized in Table 1. These spectra were recorded on a Hewlett-Packard 5950A ESCA spectrometer using the procedure described previously[6]. With the exception of the complex [Co(NH3)6]TICIt, the only previous studies on the XPS of thallium compounds have involved thallium(I) salts and the binary oxide and sulfide phases of thallium(III) [7, 8]. The thallium(Ill) phases have lower TI 4f binding energies than most thallium(I) salts. In view of the isoelectronic relationship between the pairs TI(I)-Pb(II) and TI(III)-Pb(IV), it is therefore not surprising that the Pb 4f binding energies of Pb(II) compounds may be higher[7] than those of Pb(IV), e.g. PbO > Pb02. The thallium(III) complexes of heterocyclic tertiary amines exhibit noticeably higher TI 4f binding energies than do the diethylphenylphosphine and diethyldithiocarbamate derivatives. Fhis trend presumably reflects the greater polarizability of these phosphorus and sulfur containing ligands compared to the tertiary amines, thereby leading to a greater electron density at the thallium atoms and hence to lower core electron binding energies in the case of complexes VI and VII. On the other hand, it is clearly not possible to rule out differences in relaxation
energies [9] as contributing to these chemical shifts, since this may also lead to a lowering in measured binding energies [10]. Within the present series of heterocyclic amine complexes there were no significant differences between the T1 4f binding energies, neither was there evidence that two different sets of Tl binding energies were observable for the ionic species [TICl21terpy)]÷[T1Cl4]- and [TlClz(phenh]* [T1C14(phen)] . The fwhm values of the T1 4f peaks for this terpyridyl complex (see Table l) were the same as those for TICl3(terpy), a compound which is known[ll] to be a 6-coordinate monomer. Likewise, the phenanthroline complex III, while exhibiting somewhat broader TI 4f peaks than those of the terpyridyl complexes IV and V, closely resembles [TlC13(bipy)]2 in this respect. The latter complex most likely possesses a similar structure to that of the chlorine-bridged dimer [TICl3(phen)]2[12] and thereby contains a single type of thallium environment. A final observation of note concerns the CI 2p binding energy spectrum of the complex TICl3(terpy). This compound is isomorphous with its aluminum, gallium and indium analogs[l l] and it consequently possesses a distorted octahedral structure in which the three TI-C1 bond lengths are different. Its XPS spectrum reveals a resolved C1 2Pin.3/2 doublet, a feature which implies[2] that the CI 2p energies of the different chlorine atoms are not significantly different within the present limits of instrumental resolution. A similar observation is true for the indium(Ill) complex InCI3(terpy) which was also studied in the present investigation. Its binding energies are as follows: In 3d3n.5/2 452.3 and 444.6; C1 2Pl/2.3t~ 199.3 and 197.8eV.
Acknowledgements--The assistance of Mr. Ronald E. Myers in recording the X-ray photoelectron spectra is gratefully acknow-
Table 1. X-ray photoelectron spectra of coordination complexes of thallium(IlI)~ TI Complex:~ l lI III IV V VI VII
[T1Cl~(py)2], [TICl3(bipy)]2 [TICl2(phen)2]+[TlCl,(phen)][TIC13(terpy)] [T1Cl:(terpy)] ~[TICI,] [T1CI~(PEt2Ph)25], [TI(S2CNEt2h]
4f51z 123.1 123.4 123.4 123.2 123.8 122.6 122.8
CI 4f7~2
118.7(0.9) 119.0(1.4) 119.1(1.6) 118.8(1.1) 119.3(1.1) 118.1(1.0) 118.4(1.2)
2p~/2
2p~/~
N Is
199.8 199.5 199.8 199.3 200.0 199.2 --
198.3(1.3) 198.0(1.4) 198.1(1.9) 197.8(1.4) 198.4(1.3) 197.8(1.2) --
400.0 399.5 399.3 ---399.5§
tBinding energies internally referenced to a C ls energy of 285.0 eV for the coordinated organic tigand; fwhm values given in parentheses. ~Samples of these complexes were available from earlier investigations (see refs. [3-5] and Ozimec, Smith and Walton, J. Inorg. Nucl. Chem. 38, accepted for publication (1976)). §S 2p binding energy at 162.0 eV (fwhm = 2.2 eV).
550
Notes
ledged. Support was provided by the National Science Foundation (Grant CHE74-12788A02).
Department of Chemistry Purdue University, West Lafayette IN 47907 U.S.A.
R. A. WALTON
REFERENCES
1. Part XIV: R. A. Walton, Proceedings of the Climax Second International Conference on the Chemistry and Uses of Molybdenum, Oxford, England, August 30-September 3, to be published (1977). 2. Part XIII: R. A. Walton, Coord. Chem. Revs. to be pubfished (1977).
3. R. A. Walton, Inorg. Nucl. Chem. Lett. to be pubfished (1977). 4. R. A. Walton, J. Inorg. Nucl. Chem. 32, 2875 (1970); and references therein. 5. R. A. Walton, Inorg. Chem. 7, 640 0968). 6. A. D. Hamer, D. G. Tisley and R. A. Walton, J. Inorg. Nud. Chem. 36, 1771 (1974). 7. C. K. Jcrgensen, Theoret. Chim. Acta 24, 241 (1972). 8. G. E. McGuire, G. K. Schweitzer and T. A. Carlson, Inorg. Chem. 12, 2450 (1973). 9. R. L. Martin and D. A. Shirley, J. Am. Chem. Soc. 96, 5299 (1974). 10. K. S. Kim and N. Winograd, Chem. Phys. Lett. 30, 91 (1975). 11. G. Beran, K. Dymock, H. A. Patel, A. J. Carty and P. M. Boorman, Inorg. Chem. 11, 896 (1972). 12. W. J. Baxter and G. Gafner, Inorg. Chem. 11, 176 (1972).
J+ inorg, nucl. Chem., 1977, Vol. 39, pp. 550-552. Pergamon Press. Printed in Great Britain
5- and 6-coordinate cobalt(H) isothiocyanato complexes with cyclic triamines (Received 21 June 1976) In a previous paper [1] we have reported that triazacycloalkanes, NH(CHE)p NH(CH2), NH(~H2), (p, q = 2, 3 and r = 2-6, abbreviated as pqr-cy), form either 5- or 6-coordinate isothiocyanato nickel(II) complexes [Ni(pqr-cy)(NCS)2]. The coordination number of the nickel(II) ion is determined by the size of a cyclic triamine. The small cycle with t(=p + q + r)~< 9 gave the 6-coordinate octahedral nickel(II) complexes containing a bridged NCS group, while the large cycle with t ~>9 gave 5-coordinate nickel(II) complexes. The reduction of coordination number is attributed to steric blocking of a coordination site by backbone polymethylene chains. In this paper cobalt(II) complexes of cyclic triamines are investigated to ensure the above proposition. E.V~ERIMENTAL Preparations and measurements were carried out by the methods reported previously[If. The two complexes, [Co(234cy)(NCS)2] and [Co(224-cy)(NCS):] were, however, prepared under nitrogen. The solid complexes are all stable in air. The cobalt(II) complexes prepared are given in Table 1 together with their colours and magnetic moments. On the basis of their properties discussed below, the complexes can be divided into two types in a manner similar to that for the nickel(II) complexes [1]: The three red complexes (pqr-cy = 224-cy, 234-cy and 333-cy) and the five violet complexes (pqr-cy = 225-cy, 226-cy, 235-cy, 334-cy and 336-cy) are, respectively, named the S-group and the F-group complexes. The diffuse reflectance spectra (Table 2) of the S-group complexes are mutually similar and an example is represented in Fig. 1, C. The sharp and/or weak shoulders and peaks below 8 × 103 cm ' may be overtones or combination bands of vibrational modes. The spectra are assigned on the basis of octahedral symmetry[2/: v= of Table 2 is assigned to +T,,(F)-*4T2g and (v4 and Vs) to +T,~ (F)-~ (4T~, (P), 4A2,). The absorption spectrum of
NCS
N'."
NCS
1000
5
10
N~ I
400 nm
,
i
15
20
25
x I0a c m -+
2000
200I
1000 700
500
400 nm
I
+'°fA v/
!
N
I SCN I/." NCS
500
o
5
N
700
Fig. 1. Diffuse reflectance spectra of A: [Co(235-cy)(NCS)2], B: [Co(334-cy)(NCS)2] and C: [Co(224-cy)(NCS)~].
RESULTS AND DISCUSSION
.,~.N
2000
10
15
20
25
x l 0 3 c m -I
F~. 2. Absorption spectra of A: [Co(336-cy)(NCS)~] in dichloromethane, B: [Co(334-cy)(NCS)2] in acetonitrile, and C: [Co(333-cy)(NCS)2] in dimethylsulfoxide.
Solid State Chemistry Department G. BLASSE State University G . P . M . VAN DEN HEUVEL Sorbonnelaan 4 Utrecht The Netherlands REFERENCES ~. G. Blasse, Z. Anorg. Allg. Chem. 331, 44 (1964). 2. J. M. R6au, C. Fouassier and P. Hagenmuller, Bull. Soc. Chim. (Fr.) 3873 (1967).
549
3. G. Blasse and G. P. M. van den Heuvel, Phys. Star. Sol. (a) 19, 111 (1973). 4. F. A. Krtger, Some Aspects of the Luminescence of Solids, Elsevier, Amsterdam (1948). 5. J. H. G. Bode, H. R. Kuijt, M. A. J. Th. Lahey and G Blasse. J. Solid State Chem. 8, 114 (1973). 6. G. Blasse, J. lnorg. Nucl. Chem. 37, 97 (1975). 7. L. Pauling, The Nature of the Chemical Bond, 3rd Edn. Cornell University Press, New York (1960). 8. G. Blasse and A. Bril, J. Solid State Chem. 2, 291 ! 1970}. 9. Yu. S. Leonov, Opt. Spectroscopy 9, 145 (19601.
f inorz nut! (?hem., 1977, Vol 39. pp. s49-550. Pergamon Press. Printed in Great Britain
X-Ray photoelectron spectra of inorganic molecules--XV[l, 2]. Complexes of thallium(lII) chloride (Received 28 June 1976) Our previous isolation and characterization of a variety of complexes of thallium(Ill) chloride[3,4] has led to the present investigation of the X-ray photoelectron spectra (XPS) of several such derivatives. This study was initiated to explore the possibility that in ionic complexes such as [TICl2(terpy)]+[TICl4] and [TtCl2(phen)2HTIC14(phen)] , where terpy = 2,2',2"terpyridyl[4, 5] and phen = 1 : 10-phenanthroline[3], the cationic and anionic thallium species could be distinguished by differences in their TI 4f binding energies. The appropriate XPS data for the complexes considered in the present investigation are summarized in Table 1. These spectra were recorded on a Hewlett-Packard 5950A ESCA spectrometer using the procedure described previously[6]. With the exception of the complex [Co(NH3)6]TICIt, the only previous studies on the XPS of thallium compounds have involved thallium(I) salts and the binary oxide and sulfide phases of thallium(III) [7, 8]. The thallium(Ill) phases have lower TI 4f binding energies than most thallium(I) salts. In view of the isoelectronic relationship between the pairs TI(I)-Pb(II) and TI(III)-Pb(IV), it is therefore not surprising that the Pb 4f binding energies of Pb(II) compounds may be higher[7] than those of Pb(IV), e.g. PbO > Pb02. The thallium(III) complexes of heterocyclic tertiary amines exhibit noticeably higher TI 4f binding energies than do the diethylphenylphosphine and diethyldithiocarbamate derivatives. Fhis trend presumably reflects the greater polarizability of these phosphorus and sulfur containing ligands compared to the tertiary amines, thereby leading to a greater electron density at the thallium atoms and hence to lower core electron binding energies in the case of complexes VI and VII. On the other hand, it is clearly not possible to rule out differences in relaxation
energies [9] as contributing to these chemical shifts, since this may also lead to a lowering in measured binding energies [10]. Within the present series of heterocyclic amine complexes there were no significant differences between the T1 4f binding energies, neither was there evidence that two different sets of Tl binding energies were observable for the ionic species [TICl21terpy)]÷[T1Cl4]- and [TlClz(phenh]* [T1C14(phen)] . The fwhm values of the T1 4f peaks for this terpyridyl complex (see Table l) were the same as those for TICl3(terpy), a compound which is known[ll] to be a 6-coordinate monomer. Likewise, the phenanthroline complex III, while exhibiting somewhat broader TI 4f peaks than those of the terpyridyl complexes IV and V, closely resembles [TlC13(bipy)]2 in this respect. The latter complex most likely possesses a similar structure to that of the chlorine-bridged dimer [TICl3(phen)]2[12] and thereby contains a single type of thallium environment. A final observation of note concerns the CI 2p binding energy spectrum of the complex TICl3(terpy). This compound is isomorphous with its aluminum, gallium and indium analogs[l l] and it consequently possesses a distorted octahedral structure in which the three TI-C1 bond lengths are different. Its XPS spectrum reveals a resolved C1 2Pin.3/2 doublet, a feature which implies[2] that the CI 2p energies of the different chlorine atoms are not significantly different within the present limits of instrumental resolution. A similar observation is true for the indium(Ill) complex InCI3(terpy) which was also studied in the present investigation. Its binding energies are as follows: In 3d3n.5/2 452.3 and 444.6; C1 2Pl/2.3t~ 199.3 and 197.8eV.
Acknowledgements--The assistance of Mr. Ronald E. Myers in recording the X-ray photoelectron spectra is gratefully acknow-
Table 1. X-ray photoelectron spectra of coordination complexes of thallium(IlI)~ TI Complex:~ l lI III IV V VI VII
[T1Cl~(py)2], [TICl3(bipy)]2 [TICl2(phen)2]+[TlCl,(phen)][TIC13(terpy)] [T1Cl:(terpy)] ~[TICI,] [T1CI~(PEt2Ph)25], [TI(S2CNEt2h]
4f51z 123.1 123.4 123.4 123.2 123.8 122.6 122.8
CI 4f7~2
118.7(0.9) 119.0(1.4) 119.1(1.6) 118.8(1.1) 119.3(1.1) 118.1(1.0) 118.4(1.2)
2p~/2
2p~/~
N Is
199.8 199.5 199.8 199.3 200.0 199.2 --
198.3(1.3) 198.0(1.4) 198.1(1.9) 197.8(1.4) 198.4(1.3) 197.8(1.2) --
400.0 399.5 399.3 ---399.5§
tBinding energies internally referenced to a C ls energy of 285.0 eV for the coordinated organic tigand; fwhm values given in parentheses. ~Samples of these complexes were available from earlier investigations (see refs. [3-5] and Ozimec, Smith and Walton, J. Inorg. Nucl. Chem. 38, accepted for publication (1976)). §S 2p binding energy at 162.0 eV (fwhm = 2.2 eV).
550
Notes
ledged. Support was provided by the National Science Foundation (Grant CHE74-12788A02).
Department of Chemistry Purdue University, West Lafayette IN 47907 U.S.A.
R. A. WALTON
REFERENCES
1. Part XIV: R. A. Walton, Proceedings of the Climax Second International Conference on the Chemistry and Uses of Molybdenum, Oxford, England, August 30-September 3, to be published (1977). 2. Part XIII: R. A. Walton, Coord. Chem. Revs. to be pubfished (1977).
3. R. A. Walton, Inorg. Nucl. Chem. Lett. to be pubfished (1977). 4. R. A. Walton, J. Inorg. Nucl. Chem. 32, 2875 (1970); and references therein. 5. R. A. Walton, Inorg. Chem. 7, 640 0968). 6. A. D. Hamer, D. G. Tisley and R. A. Walton, J. Inorg. Nud. Chem. 36, 1771 (1974). 7. C. K. Jcrgensen, Theoret. Chim. Acta 24, 241 (1972). 8. G. E. McGuire, G. K. Schweitzer and T. A. Carlson, Inorg. Chem. 12, 2450 (1973). 9. R. L. Martin and D. A. Shirley, J. Am. Chem. Soc. 96, 5299 (1974). 10. K. S. Kim and N. Winograd, Chem. Phys. Lett. 30, 91 (1975). 11. G. Beran, K. Dymock, H. A. Patel, A. J. Carty and P. M. Boorman, Inorg. Chem. 11, 896 (1972). 12. W. J. Baxter and G. Gafner, Inorg. Chem. 11, 176 (1972).
J+ inorg, nucl. Chem., 1977, Vol. 39, pp. 550-552. Pergamon Press. Printed in Great Britain
5- and 6-coordinate cobalt(H) isothiocyanato complexes with cyclic triamines (Received 21 June 1976) In a previous paper [1] we have reported that triazacycloalkanes, NH(CHE)p NH(CH2), NH(~H2), (p, q = 2, 3 and r = 2-6, abbreviated as pqr-cy), form either 5- or 6-coordinate isothiocyanato nickel(II) complexes [Ni(pqr-cy)(NCS)2]. The coordination number of the nickel(II) ion is determined by the size of a cyclic triamine. The small cycle with t(=p + q + r)~< 9 gave the 6-coordinate octahedral nickel(II) complexes containing a bridged NCS group, while the large cycle with t ~>9 gave 5-coordinate nickel(II) complexes. The reduction of coordination number is attributed to steric blocking of a coordination site by backbone polymethylene chains. In this paper cobalt(II) complexes of cyclic triamines are investigated to ensure the above proposition. E.V~ERIMENTAL Preparations and measurements were carried out by the methods reported previously[If. The two complexes, [Co(234cy)(NCS)2] and [Co(224-cy)(NCS):] were, however, prepared under nitrogen. The solid complexes are all stable in air. The cobalt(II) complexes prepared are given in Table 1 together with their colours and magnetic moments. On the basis of their properties discussed below, the complexes can be divided into two types in a manner similar to that for the nickel(II) complexes [1]: The three red complexes (pqr-cy = 224-cy, 234-cy and 333-cy) and the five violet complexes (pqr-cy = 225-cy, 226-cy, 235-cy, 334-cy and 336-cy) are, respectively, named the S-group and the F-group complexes. The diffuse reflectance spectra (Table 2) of the S-group complexes are mutually similar and an example is represented in Fig. 1, C. The sharp and/or weak shoulders and peaks below 8 × 103 cm ' may be overtones or combination bands of vibrational modes. The spectra are assigned on the basis of octahedral symmetry[2/: v= of Table 2 is assigned to +T,,(F)-*4T2g and (v4 and Vs) to +T,~ (F)-~ (4T~, (P), 4A2,). The absorption spectrum of
NCS
N'."
NCS
1000
5
10
N~ I
400 nm
,
i
15
20
25
x I0a c m -+
2000
200I
1000 700
500
400 nm
I
+'°fA v/
!
N
I SCN I/." NCS
500
o
5
N
700
Fig. 1. Diffuse reflectance spectra of A: [Co(235-cy)(NCS)2], B: [Co(334-cy)(NCS)2] and C: [Co(224-cy)(NCS)~].
RESULTS AND DISCUSSION
.,~.N
2000
10
15
20
25
x l 0 3 c m -I
F~. 2. Absorption spectra of A: [Co(336-cy)(NCS)~] in dichloromethane, B: [Co(334-cy)(NCS)2] in acetonitrile, and C: [Co(333-cy)(NCS)2] in dimethylsulfoxide.