Gallium hydride complexes stabilised by multidentate alkoxide ligands: precursors to thin films of Ga2O3 at low temperatures.
The donor-functionalised alkoxides {Me(3-x)N(CH(2)CH(2)O)(x)} (L(x); x = 1, 2) have been used to form gallium hydride complexes [{GaH(2)(L(1))}(2)] and [{GaH(L(2))}(2)] that are stable and isolable at room temperature. Along with a heteroleptic gallium tris(alkoxide) complex [Ga(L(1))(3)] and the dimeric complex [{GaMe(L(2))}(2)], these compounds have been used as single-source precursors for the deposition of Ga(2)O(3) by aerosol-assisted chemical vapour deposition (AACVD) with toluene as solvent. The resulting films were mostly transparent, indicating low levels of carbon contamination, and they were also mainly amorphous. However, [Ga(L(1))(3)] did contain visibly crystalline material deposited at a substrate temperature of 450 °C, by far the lowest ever observed for the CVD of gallium oxide.
Synthesis and characterization of fluorinated aminoalkoxide and iminoalkoxide gallium complexes: Application in chemical vapor deposition of Ga2O3 thin films
Gallium trichloride, GaCl3, reacts with the in situ prepared sodium salt of an aminoalkoxide or iminoalkoxide, denoted as NaL, to give the disubstituted compounds GaL2Cl, where L = OC(CF3)2CH2NMe2 (1), OC(CF3)2CH2C(Me)NMe (2). Single-crystal X-ray diffraction studies on 1 and 2 indicated the formation of a trigonal-bipyramidal structure with chloride and alkoxy groups occupying the equatorial sites and the nitrogen donors located at the axial positions. For the related trimethylgallium reagent GaMe3, addition of an equal amount of amino alcohol LH induced the elimination of methane to afford the complexes GaMe2L, where L = OC(CF3)2CH2NHMe (3), OC(CF3)2CH2NHBut (4), OC(CF3)2CH2NMe2 (5), in high yields. The crystal structure of 5 was determined by X-ray diffraction, showing a distorted-tetrahedral framework which differs greatly from that observed in the trigonal-bipyramidal Ga complexes 1 and 2. Variable-temperature 1H NMR studies on 3 and 4 indicated the occurrence of rapid N→Ga bond scission, followed by...
To What Extent Can English-as-a-Second Language Learners Read Economic News Texts?
In decision making in the economic field, an especially important requirement is to rapidly understand news to absorb ever-changing economic situations. Given that most economic news is written in English, the ability to read such information without waiting for a translation is particularly valuable in economics in contrast to other fields. In consideration of this issue, this research investigated the extent to which non-native English speakers are able to read economic news to make decisions accordingly – an issue that has been rarely addressed in previous studies. Using an existing standard dataset as training data, we created a classifier that automatically evaluates the readability of text with high accuracy for English learners. Our assessment of the readability of an economic news corpus revealed that most news texts can be read by intermediate English learners. We also found that in some cases, readability varies considerably depending on the knowledge of certain words specific to the economic field.