Structure and Stability of Noble Gas Bound EX 1 3 Compounds (E 5 C, Ge, Sn, Pb; X 5 H, F, Cl, Br) Sudip Pan AQ9 , [a] Diego Moreno, [b] Sreyan Ghosh, [a] Pratim K. Chattaraj,* [a] and Gabriel Merino AQ1 [b] It has been analyzed at the MP2/def2-QZVPPD level whether EX 1 3 (E 5 C-Pb; X 5 H, F-Br) can bind noble gas atoms. Geomet- rical and electronic structures, dissociation energy values, ther- mochemical parameters, natural bond order, electron density, and energy decomposition analyses highlight the possibility of such noble gas bound EX 1 3 compounds. Except He and Ne, the other heavier congeners of this family make quite strong bonds with E. In fact, the dissociations of Ar-Rn bound ana- logues turn out to be endergonic in nature at 298 K, except in the cases of ArGeCl 1 3 , Ar=KrGeBr 1 3 , and ArSnBr 1 3 . GeH 1 3 and EF 1 3 (E 5 Ge-Pb) can even bind two Ng atoms with reasonably high dissociation energy. As the p z orbital of the E center in EX 1 3 plays a crucial role in its binding with the noble gas atoms, the effect of the p back-bonding causing X ! E elec- tron transfer ought to be properly understood. Due to the larger back-donation, the Ng binding ability of EX 1 3 gradually decreases along F to Br. EH 1 2 and the global minimum HE 1... H 2 (E 5 Sn, Pb) complexes are also able to bind Ar-Rn atoms quite effectively. The NgAE bonds in Ar-Rn bound CH 1 3 , GeH 1 3 , and EF 1 3 (E 5 Ge-Pb) and Xe/RnAE bonds in NgECl 1 3 and NgEBr 1 3 (E 5 Ge, Sn) are mainly of covalent type. V C 2015 Wiley Periodicals, Inc. DOI: 10.1002/jcc.23986 Introduction The development of noble gas chemistry is now in full swing as authenticated by the speed at which several noble gas (Ng) com- pounds are being reported by experimentalists [1–5] and theoreti- cians. [6–11] If we look at the Ng compounds having group 14 elements, several of them with NgAC bonds can be found, which were experimentally detected in a cryogenic condition by matrix- isolation technique. The detection of XeCH 1 3 in mass spectrum via ion-molecule reactions is the first example of having an NgAC bond. [12a] Thereafter, KrCH 1 3 and ArCH 1 3 were also detected using the same technique. [12b] The molecules like Xe(CF 3 ) 2 , [13] [C 6 F 5 Xe][B(C 6 F 5 ) 3 F], [14] [MeCN-Xe-C 6 F 5 ] 1 , [15] [C 6 F 5 Xe] 1 [C 6 F 5 BF 3 ] 2 , [16] HXeCCH, [17a–c] HKrCCH, [17c] HXeCC, [17a,17c] HXeCCXeH, [17a,17c] HXeCN, [1d] HKrCN, [1d] HNgCCF, [17d] HCCNgF, [17d] ClXeCN, [17e] BrXeCN, [17e] HXeC 3 N, [17f ] HKrC 3 N, [17f ] HXeC 4 H, [1j] and HKrC 4 H [1j] are some of the examples in this category. Moreover, the number of the computationally predicted Ng-C compounds is even larger than this. [18] Some unusual systems like highly coordinated Ng(CCH) 4 and Ng(CCH) 6 (Ng 5 Kr, Xe) [19a] and polymeric H-(Xe-C 2 ) n - Xe-H (n  1) [19b] were also found to be minima on the respective potential energy surfaces (PESs). However, there are only a few candidates with NgASi bonds, which were either experimentally detected or theoreti- cally predicted. In 1995, the detection of F 3 SiXe 1 by Cipollini and Grandinetti [20] through mass spectrometry, originating from the nucleophilic displacement of HF by Xe from proto- nated SiF 4 , is the first example of species having SiANg bonds. Six years later, Cunje et al. [21] produced F 3 SiKr 1 and F 3 SiAr 1 in the gas phase. They also found that the structural arrange- ments like F 2 SiNgF 1 and FSiFNgF 1 belong to minima on the corresponding PESs, and are higher energy isomers in compar- ison to F 3 SiNg 1 . [21] Recently, doubly positively charged ArSiF 21 2 and NeSiF 21 2 species were also detected by Roithov a and Schr€ oder. [22] Moreover, few inserted compounds like FXeSiF, FArSiF 3 , and FKrSiF 3 were reported to be metastable sys- tems. [23] The stability and bonding situations in NgSiX 1 3 (X 5 H, F, Cl, Br) were also studied quite recently. [7h] The number of reported systems having GeANg bonds is even smaller than that of having SiANg bonds. In 2010, Gran- dinetti and coworkers [24] were the first to detect F 3 Ge-Xe 1 in gas phase by mass spectrometric technique. Yockel et al. [25] theoretically analyzed the metastability of FKrGeF 3 . Moreover, Grandinetti and coworkers [26] also found that FXeGeF and FXe- GeF 3 are also metastable in nature. More recently, we studied the metastability of FNgEF and FNgEF 3 (E 5 Sn, Pb) com- pounds having NgASn/Pb covalent bonds. [27] In this study, in continuation to our earlier investigation on Ng n SiX 1 3 , [7h] we have considered the complete series of EX 1 3 (X 5 H, F-Br) containing heavier congeners of Si as well as C analogues to explore their Ng binding ability. For SnH 1 3 and PbX 1 3 (X 5 H, Cl, Br), the corresponding D 3h isomer is not a global minimum rather Sn/PbX 1... X 2 isomer is the global mini- mum. (we have also performed the global minima search of EX 1 3 compound and have found that in addition to SnH 1 3 and [a] S. Pan, S. Ghosh, P. K. Chattaraj Department of Chemistry and Centre for Theoretical Studies, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India AQ6 E-mail: pkc@chem.iitkgp.ernet.in AQ7 [b] D. Moreno, G. Merino Departamento de F  ısica Aplicada, Centro de Investigaci  on y de Estudios Avanzados, Unidad M erida. Km 6 Antigua Carretera a Progreso. Apdo. Postal 73, Cordemex, M erida, Yucatan 97310, M exico E-mail: gmerino@mda.cinvestav.mx Contract grant sponsor: Conacyt; Contract grant number: INFRA-2013- 01-204586 (to D.M.); Contract grant sponsor: Moshinsky Foundation AQ8 V C 2015 Wiley Periodicals, Inc. Journal of Computational Chemistry 2015, DOI: 10.1002/jcc.23986 1 FULL PAPER WWW.C-CHEM.ORG J_ID: JCC Customer A_ID: JCC23986 Cadmus Art: JCC23986 Ed. Ref. No.: 15-0194.R1 Date: 23-June-15 Stage: Page: 1 ID: vedhanarayanan.m Time: 12:22 I Path: //10.18.11.53/home$/vedhanarayanan.m$/JW-JCCT150122