The stoichiometric reactions of antimony trichloride, trimethylsilyl trifluoromethanesulfonate, and diiminopyridine ligands lead to the formation of N , N ′, N ′′-chelated SbCl 2 cationic complexes. Methyl and phenyl substituents on the imine carbons of the ligand yielded structures with a lone pair on antimony and the hydrogen substituted variant was notably different as it forms a Menshutkin complex with meta -xylene in the solid-state.
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Assessing the donor ability of boratabenzene and 9-borataphenanthrene anions through metal complexes with carbonyl ligands
A series of anionic group 6 tricarbonyl and neutral rhodium dicarbonyl complexes featuring a boratabenzene (L1, with a phenyl on boron, a trimethylsilyl group on the adjacent carbon and methyl groups on the other carbons) and a borataphenanthrene ligand (L2, with a phenyl group on boron and a trimethylsilyl group on the adjacent carbon) are prepared. The donor ability of the boracyclic ligands is evaluated experimentally and theoretically by the stretching frequencies of the CO ancillary ligands. Overall, the donor ability of the ligands falls into the following trend: L1 > cyclopentadienyl > L2 > mesitylene.
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- Award ID(s):
- 1753025
- PAR ID:
- 10406058
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 51
- Issue:
- 45
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 17216 to 17223
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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null (Ed.)Behavioral studies on language processing rely on the eye-mind assumption, which states that the time spent looking at text is an index of the time spent processing it. In most cases, relatively shorter reading times are interpreted as evidence of greater processing efficiency. However, previous evidence from L2 research indicates that non-native participants who present fast reading times are not always more efficient readers, but rather shallow parsers. Because earlier studies did not identify a reliable predictor of variability in L2 processing, such uncertainty around the interpretation of reading times introduces a potential confound that undermines the credibility and the conclusions of online measures of processing. The present study proposes that a recently developed modulator of online processing efficiency, namely, chunking ability, may account for the observed variability in L2 online reading performance. L1 English – L2 Spanish learners’ eye movements were analyzed during natural reading. Chunking ability was predictive of overall reading speed. Target relative clauses contained L2 Verb-Noun multiword units, which were manipulated with regards to their L1-L2 congruency. The results indicated that processing of the L1-L2 incongruent units was modulated by an interaction of L2 chunking ability and level of knowledge of multiword units. Critically, the data revealed an inverse U-shaped pattern, with faster reading times in both learners with the highest and the lowest chunking ability scores, suggesting fast integration in the former, and lack of integration in the latter. Additionally, the presence of significant differences between conditions was correlated with individual chunking ability. The findings point at chunking ability as a significant modulator of general L2 processing efficiency, and of cross-language differences in particular, and add clarity to the interpretation of variability in the online reading performance of non-native speakers.more » « less
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null (Ed.)Successful listening in a second language (L2) involves learning to identify the relevant acoustic–phonetic dimensions that differentiate between words in the L2, and then use these cues to access lexical representations during real-time comprehension. This is a particularly challenging goal to achieve when the relevant acoustic–phonetic dimensions in the L2 differ from those in the L1, as is the case for the L2 acquisition of Mandarin, a tonal language, by speakers of non-tonal languages like English. Previous work shows tone in L2 is perceived less categorically (Shen and Froud, 2019) and weighted less in word recognition (Pelzl et al., 2019) than in L1. However, little is known about the link between categorical perception of tone and use of tone in real time L2 word recognition at the level of the individual learner. This study presents evidence from 30 native and 29 L1-English speakers of Mandarin who completed a real-time spoken word recognition and a tone identification task. Results show that L2 learners differed from native speakers in both the extent to which they perceived tone categorically as well as in their ability to use tonal cues to distinguish between words in real-time comprehension. Critically, learners who reliably distinguished between words differing by tone alone in the word recognition task also showed more categorical perception of tone on the identification task. Moreover, within this group, performance on the two tasks was strongly correlated. This provides the first direct evidence showing that the ability to perceive tone categorically is related to the weighting of tonal cues during spoken word recognition, thus contributing to a better understanding of the link between phonemic and lexical processing, which has been argued to be a key component in the L2 acquisition of tone (Wong and Perrachione, 2007).more » « less
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Introduction Listeners rapidly “tune” to unfamiliar accented speech, and some evidence also suggests that they may improve over multiple days of exposure. The present study aimed to measure accommodation of unfamiliar second language- (L2-) accented speech over a consecutive 5-day period using both a measure of listening performance (speech recognition accuracy) and a measure of cognitive load (a dual-task paradigm).
Methods All subjects completed a dual-task paradigm with L1 and L2 accent on Days 1 and 5, and were given brief exposure to either L1 (control group) or unfamiliar L2 (training groups) accent on Days 2–4. One training group was exposed to the L2 accent via a standard speech transcription task while the other was exposed to the L2 accent via a transcription task that included implicit feedback (i.e., showing the correct answer after each trial).
Results Although overall improvement in listening performance and reduction in cognitive load were observed from Days 1 to 5, our results indicated neither a larger benefit for the L2 accent training groups compared to the control group nor a difference based on the implicit feedback manipulation.
Discussion We conclude that the L2 accent trainings implemented in the present study did not successfully promote long-term learning benefits of a statistically meaningful magnitude, presenting our findings as a methodologically informative starting point for future research on this topic.
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This study investigates pronoun interpretation by second language (L2) learners of English, focusing on whether first language (L1) transfer and/or processing difficulty affect L2 learners’ pronoun resolution. It is hypothesized that L2 learners’ non-target performance in L2-pronoun interpretation is attributable to two sources. The first is the computational complexity required for pronoun resolution, as argued in L1 acquisition by Grodzinsky and Reinhart and L2 acquisition by Slabakova et al. The second is how pronoun interpretation operates in L1. The hypothesis is tested by comparing Korean and Spanish L2-English learners’ interpretation of English pronouns using a Truth Value Judgment Task. Both groups had difficulty rejecting pronouns with local-referential antecedents when their proficiency levels were low. Additionally, Korean speakers showed more non-target responses than Spanish speakers due to their knowledge of pronoun interpretation in Korean. These results indicate that both L1 transfer and processing difficulty may be sources of L2 learners’ non-target pronoun interpretation, supporting the hypothesis of the study.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2dt02795j
