Reactions of Atomic Silicon and Germanium with Ammonia:  A Matrix-Isolation FTIR and Theoretical Study

Chen, Mohua; Zheng, Aihua; Lu, Hao; Zhou, Mingfei

doi:10.1021/jp012928z

Cited by 30 publications

(35 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Similar to previous studies [7][8][9][10], the most stable imine silylene HN=Si is also in singlet state possessing a linear structure, where the singlet state is more favorable about 317 kJ/mol in energy relative to that of triplet state at the B3LYP/6-311+G* level of theory. Thus, the singlet state of HN=Si has been discussed in the following study.…”

Section: Resultssupporting

confidence: 85%

“…Much attention has been paid to the chemistry of silylenes and many stable silylenes have been experimentally synthesized [2][3][4][5][6][7][8][9][10]. Similarly, analogous to carbenoids, silylenoids can be also formed between silylenes and inorganic salts (like, NaF), which can be denoted as R 1 R 2 SiMX (M = alkali metal, X = halogen atom usually).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Probing the imine silylenoid HN=SiNaF and its insertions reaction with R–H (R=F, OH, NH2, CH3) using DFT

Tan

Wang

et al. 2008

Struct Chem

View full text Add to dashboard Cite

The geometries and isomerization of the imine silylenoid HN=SiNaF as well as its insertion reactions with some R-H molecules have been systematically investigated theoretically, where R=F, OH, NH 2 , and CH 3 , respectively. The barrier heights for the four insertion reactions are 67.7, 115.6, 153.5, and 271.5 kJ/mol at the B3LYP/6-311+G* level of theory, respectively. Here, all the mechanisms of the four reactions are identical to each other, i.e., a stable intermediate has been formed during the insertion reaction. Then, the intermediate could dissociate into the substituted silylene (HN=SiHR) and NaF with a barrier corresponding to their respective dissociation energies. Correspondingly, the reaction energies for the four reactions are 71.8, 95.5, 123.3, and 207.6 kJ/mol, respectively, which are linearly correlated with the calculated barrier heights. Furthermore, the effects of halogen substitutions (F, Cl, and Br) on the reaction activity have also been discussed. As a result, the relative reactivity among the four insertion reactions should be as follows: H-F [ H-OH [ H-NH 2 [ H-CH 3 .

show abstract

Section: Resultssupporting

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Probing the imine silylenoid HN=SiNaF and its insertions reaction with R–H (R=F, OH, NH2, CH3) using DFT

Tan

Wang

et al. 2008

Struct Chem

View full text Add to dashboard Cite

show abstract

“…On scanning the PES along the coordinate of Si-N-H bending from 120°to 180°under a constraint of point group C s , at ∠Si-N-H ≈ 143.5°, the calculated electron configuration of H 2 SiNH + abruptly alters from the 2 A′′ to the 2 A′ state. As for the H 2 SiNH system, HSiNH 2 has a planar equilibrium geometry for the 1 A′ ground state that lies 1.75 eV lower than the 3 A′′ state; Chen et al 17 assigned the 3 A′′ state to 3 A′. In contrast to H 2 SiNH + , in its ground state, HSiNH 2 + has an equilibrium structure belonging to point group C s rather than C 2V .…”

Section: Resultsmentioning

confidence: 99%

“…[18][19][20][21][22] Several calculations [17][18][19][20][23][24][25][26][27][28][29][30][31][32][33] were devoted to the electronic energies of various silicon-nitrogen hydrides. Apart from experiments already mentioned, 17 Chen et al 17 used density functionals of type B3LYP to calculate potential energy surfaces (PESs) for the reaction of Si ( 3 P, 1 D) with NH 3 , including intermediates SiNH 3 , HSiNH 2 , H 2 SiNH, and transition structures. 17 Using the Gaussian-2 (G2) method, Goldberg et al 20 calculated the PESs of neutral and cationic systems of H 2 SiN, HSiNH, and SiNH 2 and transition structures between isomers.…”

Section: Introductionmentioning

confidence: 99%

“…Apart from experiments already mentioned, 17 Chen et al 17 used density functionals of type B3LYP to calculate potential energy surfaces (PESs) for the reaction of Si ( 3 P, 1 D) with NH 3 , including intermediates SiNH 3 , HSiNH 2 , H 2 SiNH, and transition structures. 17 Using the Gaussian-2 (G2) method, Goldberg et al 20 calculated the PESs of neutral and cationic systems of H 2 SiN, HSiNH, and SiNH 2 and transition structures between isomers. Luke et al 23 calculated the electronic energies of neutral HSiN, H 3 SiN, and their isomers using the 6-31G* basis set and Moller-Plesset perturbation theory with single, double, triple, and quadruple substitution [MP4(SDTQ)].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigations of Silicon−Nitrogen Hydrides from Reaction of Nitrogen Atoms with Silane: Experiments and Calculations

Chen

Chaudhuri

et al. 2008

J. Phys. Chem. A

View full text Add to dashboard Cite

Using a quadrupole mass filter and vacuum-ultraviolet ionization, we measured the time-of-flight spectra of species at mass-to-charge ratios of m/ z = 45-42 from the reaction of N + SiH 4 in crossed molecular beams. Species with m/ z = 44 and 43 correspond to reaction products HSiNH/SiNH 2 and HSiN/HNSi, respectively; species with m/ z = 45 and 42 are assigned to isotopic variants and daughter ions, respectively, of those two reaction products. We measured the photoionization yields and branching ratios for dissociative ionization of reaction products as a function of photoionization energy. The ionization thresholds of products HSiNH/SiNH 2 and HSiN/HNSi were determined to be 6.7 and 9.2 eV, respectively. Furthermore, we calculated the equilibrium structures, electronic energies, and vibrational wavenumbers of various silicon-nitrogen hydrides H x SiNH y ( x + y = 0-3) using quantum-chemical methods. SiNH 2 (X (2)B 2) and HNSi (X (1)Sigma (+)) are more stable than HSiNH (X (2)A') and HSiN (X (1)Sigma (+)) by 0.82 and 2.81 eV, respectively. SiNH 2 (X (2)B 2), HSiNH (X (2)A'), HNSi (X (1)Sigma (+)), and HSiN (X (1)Sigma (+)) have adiabatic ionization energies of 6.81, 8.19, 10.21, and 10.23 eV, respectively. These experimental and calculated results indicate that SiNH 2 (X (2)B 2) and HNSi (X (1)Sigma (+)) are dominant among isomeric products in the reaction of N + SiH 4. This work presents the first observation of products from the reaction of N + SiH 4 in crossed beams and extensive calculations on pertinent silicon-nitrogen hydrides.

show abstract

Short‐Lived Intermediates

Almond¹,

Jenkins²

2005

Encyclopedia of Inorganic Chemistry

View full text Add to dashboard Cite

Methods for the generation and detection of short‐lived intermediates are discussed. These include flow systems (where a steady‐state concentration of the intermediate is monitored), flash photolysis (where the intermediate is studied in real time using a very fast detection method), and matrix isolation (where the intermediate is preserved by trapping in a solid, inert host at low temperature and where conventional spectroscopic methods are used for detection). Many of the classical experiments utilizing these methods are described, but the relevance to modern chemical studies is also emphasized. The spectroscopic methods used to detect short‐lived intermediates are considered. These include nuclear magnetic resonance (NMR), electron spin resonance (ESR), microwave, infrared (IR), Raman, and ultraviolet‐visible absorption and emission spectroscopies. It is shown that IR remains the method of choice for matrix‐isolation experiments whereas flash photolysis work tends to rely mainly upon electronic spectroscopic techniques. The use of IR spectroscopy, using tunable lasers, for flash photolysis work (at least for slightly longer‐lived intermediates) is discussed. Finally two case studies are considered in detail. These are the photolysis of metal carbonyls and the formation of unusual main group compounds at high temperatures. These studies exemplify the procedures that have been used to investigate short‐lived intermediates in inorganic chemistry.

show abstract

Reactions of Atomic Silicon and Germanium with Ammonia: A Matrix-Isolation FTIR and Theoretical Study

Cited by 30 publications

References 34 publications

Probing the imine silylenoid HN=SiNaF and its insertions reaction with R–H (R=F, OH, NH2, CH3) using DFT

Probing the imine silylenoid HN=SiNaF and its insertions reaction with R–H (R=F, OH, NH2, CH3) using DFT

Investigations of Silicon−Nitrogen Hydrides from Reaction of Nitrogen Atoms with Silane: Experiments and Calculations

Short‐Lived Intermediates

Contact Info

Product

Resources

About