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1.
BMC Geriatr ; 24(1): 362, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654157

ABSTRACT

BACKGROUND: Societal attitudes toward ageing play a significant role in shaping one's ageing experience, and an age-friendly environment can potentially enhance the life satisfaction of older individuals. The objective of this study is to examine the role of attitudes to ageing as mediators in the association between the perception of an age-friendly city and life satisfaction among middle-aged and older adults. METHODS: Using the tools of Age-Friendly City (AFC) criteria, Attitudes to Ageing Questionnaire (AAQ) to measure psychosocial loss, psychological growth, and physical change, and Satisfaction with Life Scale (SWLS) to assess the level of life satisfaction among community-dwelling middle-aged and older people in Macao. Multiple mediation analysis was performed to test the mediation effect. RESULTS: A total of 543 participants were included in this study. The average score of AFC was 4.25, the total scores of psychosocial loss, physical change, and psychological growth were 24.06, 29.00, and 26.94 respectively. The total score of SWLS was 24.06. There was a partial mediation of attitudes to ageing in the relationship between perception of age-friendly city and life satisfaction. The mediation effect explained 56.1% of the total effect of AFC to life satisfaction. CONCLUSION: The development of an age-friendly city can help improve the public's view on ageing, and thus improve their life satisfaction. It is important for government to consider the improvement of people's attitudes to ageing when developing policies regarding AFC.


Subject(s)
Aging , Personal Satisfaction , Humans , Male , Female , Aged , Middle Aged , Cross-Sectional Studies , Aging/psychology , Aging/physiology , Macau , Surveys and Questionnaires , Cities , Independent Living/psychology , Attitude , Aged, 80 and over
2.
J Phys Chem Lett ; 14(34): 7626-7631, 2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37602768

ABSTRACT

Electrostatic interactions between the zeolite cavity and confined noble-metal nanoparticles govern the photophysical properties of these materials. A better understanding of these interactions can afford new perspectives in optoelectronics applications. We investigated this interplay by revealing the peculiar photophysical properties of Ag clusters embedded in nanosized faujasite zeolite structures. Crystal size and steady state optical properties were characterized via integrated light and electron microscopy (ILEM) and steady state spectroscopy. Extensive time-resolved spectroscopy experiments performed on femtosecond to millisecond time scales revealed excited state dynamics that are intriguingly different from those observed for their micrometer sized counterpart. Multiscale modeling investigations were performed to rationalize the effect of the crystal size on the photophysical properties. Our results indicate that for the nanosized crystals, the emissive properties as well as the radiative and nonradiative processes involving the Ag clusters are dramatically dependent on the surface charge density and surface charge balance.

3.
Heliyon ; 9(5): e16009, 2023 May.
Article in English | MEDLINE | ID: mdl-37187906

ABSTRACT

Background: The field of language teaching and learning has long recognized the role of vocabulary knowledge in all aspects of language proficiency and indicated that vocabulary beliefs and learning strategies play a pivotal role in learners' vocabulary development. As a result, understanding learners' beliefs and strategies in vocabulary learning is of paramount importance to language teachers. The Vocabulary Learning Questionnaire (VLQ) developed by Peter Gu in 2018 could be considered the most recent, validated instrument for the measurement of vocabulary learning beliefs and strategies. However, the VLQ contains too many items and is only available in English. The objectives of the study, therefore, are (1) to develop and validate a Vietnamese version of the VLQ which can exclude construct-irrelevant noises related to L2 comprehension, and (2) to reduce the number of items while retaining the key factors in the instruments. Methods: 722 Vietnamese university students took part in the study. Exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) were examined with the free software Jamovi 2.3.13. Both Cronbach's alpha and McDonald's omega were employed to evaluate the factors' internal consistency. Results: Separate EFAs confirmed the two dimensions of vocabulary beliefs, explaining 62.6% of the total variance, and seven factors of vocabulary strategies, predicting 72.1% of the total variance. CFAs confirmed the hypothesized 9-dimensional structures of different vocabulary learning beliefs and strategies and offer cross-validation evidence for the Vietnamese VLQ. Reliability metrics demonstrated acceptable internal reliability for vocabulary belief and strategy sub-scales. Conclusion: The Vietnamese VLQ provides a validated measure of vocabulary beliefs and strategies. The 30-item version of the Vietnamese VLQ serves as a starting point for future research in the field of vocabulary learning and teaching in Vietnam.

4.
BMJ Open ; 13(3): e064870, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36918251

ABSTRACT

OBJECTIVES: To compare the accuracy of the Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II) Scores in predicting mortality among intensive care unit (ICU) patients with sepsis in a low-income and middle-income country. DESIGN: A multicentre, cross-sectional study. SETTING: A total of 15 adult ICUs throughout Vietnam. PARTICIPANTS: We included all patients aged ≥18 years who were admitted to ICUs for sepsis and who were still in ICUs from 00:00 to 23:59 of the specified study days (ie, 9 January, 3 April, 3 July and 9 October of the year 2019). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was hospital all-cause mortality (hospital mortality). We also defined the secondary outcome as all-cause deaths in the ICU (ICU mortality). RESULTS: Of 252 patients, 40.1% died in hospitals, and 33.3% died in ICUs. SOFA Score (areas under the receiver operating characteristic curve (AUROC): 0.688 (95% CI 0.618 to 0.758); cut-off value≥7.5; PAUROC<0.001) and APACHE II Score (AUROC: 0.689 (95% CI 0.622 to 0.756); cut-off value ≥20.5; PAUROC<0.001) both had a poor discriminatory ability for predicting hospital mortality. However, the discriminatory ability for predicting ICU mortality of SOFA (AUROC: 0.713 (95% CI 0.643 to 0.783); cut-off value≥9.5; PAUROC<0.001) was fair and was better than that of APACHE II Score (AUROC: 0.672 (95% CI 0.603 to 0.742); cut-off value≥18.5; PAUROC<0.001). A SOFA Score≥8 (adjusted OR (AOR): 2.717; 95% CI 1.371 to 5.382) and an APACHE II Score≥21 (AOR: 2.668; 95% CI 1.338 to 5.321) were independently associated with an increased risk of hospital mortality. Additionally, a SOFA Score≥10 (AOR: 2.194; 95% CI 1.017 to 4.735) was an independent predictor of ICU mortality, in contrast to an APACHE II Score≥19, for which this role did not. CONCLUSIONS: In this study, SOFA and APACHE II Scores were worthwhile in predicting mortality among ICU patients with sepsis. However, due to better discrimination for predicting ICU mortality, the SOFA Score was preferable to the APACHE II Score in predicting mortality.Clinical trials registry - India: CTRI/2019/01/016898.


Subject(s)
Organ Dysfunction Scores , Sepsis , Adult , Humans , Cross-Sectional Studies , Intensive Care Units , Prognosis , Retrospective Studies , ROC Curve , Southeast Asian People , Vietnam/epidemiology
5.
PLoS One ; 17(10): e0275739, 2022.
Article in English | MEDLINE | ID: mdl-36240177

ABSTRACT

BACKGROUND: The simple scoring systems for predicting the outcome of sepsis in intensive care units (ICUs) are few, especially for limited-resource settings. Therefore, this study aimed to evaluate the accuracy of the quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) score in predicting the mortality of ICU patients with sepsis in Vietnam. METHODS: We did a multicenter cross-sectional study of patients with sepsis (≥18 years old) presenting to 15 adult ICUs throughout Vietnam on the specified days (i.e., 9th January, 3rd April, 3rd July, and 9th October) representing the different seasons of 2019. The primary and secondary outcomes were the hospital and ICU all-cause mortalities, respectively. The area under the receiver operating characteristic curve (AUROC) was calculated to determine the discriminatory ability of the qSOFA score for deaths in the hospital and ICU. The cut-off value of the qSOFA scores was determined by the receiver operating characteristic curve analysis. Upon ICU admission, factors associated with the hospital and ICU mortalities were assessed in univariable and multivariable logistic models. RESULTS: Of 252 patients, 40.1% died in the hospital, and 33.3% died in the ICU. The qSOFA score had a poor discriminatory ability for both the hospital (AUROC: 0.610 [95% CI: 0.538 to 0.681]; cut-off value: ≥2.5; sensitivity: 34.7%; specificity: 84.1%; PAUROC = 0.003) and ICU (AUROC: 0.619 [95% CI: 0.544 to 0.694]; cutoff value: ≥2.5; sensitivity: 36.9%; specificity: 83.3%; PAUROC = 0.002) mortalities. However, multivariable logistic regression analyses show that the qSOFA score of 3 was independently associated with the increased risk of deaths in both the hospital (adjusted odds ratio, AOR: 3.358; 95% confidence interval, CI: 1.756 to 6.422) and the ICU (AOR: 3.060; 95% CI: 1.651 to 5.671). CONCLUSION: In our study, despite having a poor discriminatory value, the qSOFA score seems worthwhile in predicting mortality in ICU patients with sepsis in limited-resource settings. CLINICAL TRIAL REGISTRATION: Clinical trials registry-India: CTRI/2019/01/016898.


Subject(s)
Organ Dysfunction Scores , Sepsis , Adolescent , Adult , Asian People , Cross-Sectional Studies , Hospital Mortality , Humans , Intensive Care Units , Prognosis , ROC Curve , Retrospective Studies , Sepsis/diagnosis , Vietnam/epidemiology
6.
Phys Chem Chem Phys ; 24(36): 21822-21832, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36063116

ABSTRACT

Formation and stability of the B56 boron cluster were investigated using a topological approach and the disk aromaticity model. An extensive global energy minimum search for the B56 system which was carried out by means of the Mexican Enhanced Genetic Algorithm (MEGA) in conjunction with density functional theory computations, confirms a quasi-planar structure as its energetically most stable isomer. Such a structural motif is derived by applying a topological leapfrog operation to a B12 form. Its high thermodynamic stability can be explained by the disk aromaticity model in which the delocalization of its π orbitals can be assigned to the levels of a particle in a circular box with the [(1σ)2 (1π)4 (1δ)4 (1φ)4 (2σ)2 (1γ)4 (2π)4 (2δ)4 (1η)4 (2φ)4 (1θ)2] electronic configuration. This π delocalization is confirmed by other delocalization indices. While the B56 has a similar electron delocalization to that of the quasi-planar B50, they have opposite magnetic ring current properties because of the symmetry selection rules of their HOMO-LUMO electronic transitions. The π delocalization in the boron clusters is larger at long distances as compared to carbon clusters at similar sizes, but such a trend is reversed at shorter distances.

7.
Heliyon ; 8(8): e10244, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36042732

ABSTRACT

The vocabulary levels tests (VLT) are very powerful instruments for the measurement of learners' vocabulary knowledge and have been widely used by language teachers in the task of matching learners to their reading materials. However, their accompanying score interpretation methods have not been backed by research and concerns have been raised regarding these scoring methods' appropriateness. The study began by looking at the VLTs and their scoring methods since the day they were born and then went on to investigate potential issues in the scoring methods that have been used together with the VLTs: the cut-off score and vocabulary size score. Tests of receptive vocabulary knowledge and English reading proficiency were administered to 234 university students. Research findings problematized the application of VLTs and cut-off scores on the ranking of large groups of students and supported the use of vocabulary size score as a more suitable method for vocabulary knowledge research. Implications for teaching and learning were also provided.

8.
Chem Commun (Camb) ; 58(38): 5785-5788, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35451431

ABSTRACT

The Au17 gold cluster was experimentally produced in the gas phase and characterized by its vibrational spectrum recorded using far-IR multiple photon dissociation (FIR-MPD) of Au17Kr. DFT and coupled-cluster theory PNO-LCCSD(T)-F12 computations reveal that, at odds with most previous reports, Au17 prefers two star-like forms derived from a pentaprism added by two extra Au atoms on both top and bottom surfaces of the pentaprism, along with five other Au atoms each attached on a lateral face. A good agreement between calculated and FIR-MPD spectra indicates a predominant presence of these star-like isomers. Stabilization of a star form arises from strong orbital interactions of an Au12 core with a five-Au-atom string.

9.
Front Psychol ; 13: 800983, 2022.
Article in English | MEDLINE | ID: mdl-35282246

ABSTRACT

The present study analyzed the vocabulary profile of the News on the Web (NOW) corpus, which contained 12 billion words from online newspapers and magazines in 20 countries to determine the vocabulary knowledge needed to reasonably understand online newspaper and magazine articles. The results showed that, in general, knowledge of the most frequent 4,000 word families in the British National Corpus/Corpus of Contemporary American English (BNC/COCA) wordlist plus proper nouns, marginal words, transparent compounds and acronyms was necessary to gain 95% coverage for the NOW corpus. However, when it came to the 98% coverage, online newspaper and magazine articles from different countries had relatively distinct lexical demands. In-depth analyses were carried out and the findings offered comprehensive insights into the issue. Implications for teaching and learning were also provided.

10.
Front Psychol ; 13: 831684, 2022.
Article in English | MEDLINE | ID: mdl-35265018

ABSTRACT

The article presents a methodological update on the lexical profile of informal spoken English with the emphasis on movies, television programs, and soap operas. The study analyzed Mark Davies's mega-corpora with data containing approximately 625 million words and employed Paul Nation's comprehensive and up-to-date British National Corpus/Corpus of Contemporary American English (BNC/COCA) wordlists. Data from the analyses showed that viewers would need a vocabulary knowledge at 3,000 and 5,000 words frequency levels to understand 95 and 98% of the words in scripted dialogs, respectively. Soap operas were found to be less lexically demanding compared to TV programs and movies. Findings are expected to fill in the methodological gaps between vocabulary assessment and vocabulary profiling research.

11.
Sci Rep ; 11(1): 18924, 2021 09 23.
Article in English | MEDLINE | ID: mdl-34556710

ABSTRACT

Sepsis is the most common cause of in-hospital deaths, especially from low-income and lower-middle-income countries (LMICs). This study aimed to investigate the mortality rate and associated factors from sepsis in intensive care units (ICUs) in an LMIC. We did a multicenter cross-sectional study of septic patients presenting to 15 adult ICUs throughout Vietnam on the 4 days representing the different seasons of 2019. Of 252 patients, 40.1% died in hospital and 33.3% died in ICU. ICUs with accredited training programs (odds ratio, OR: 0.309; 95% confidence interval, CI 0.122-0.783) and completion of the 3-h sepsis bundle (OR: 0.294; 95% CI 0.083-1.048) were associated with decreased hospital mortality. ICUs with intensivist-to-patient ratio of 1:6 to 8 (OR: 4.533; 95% CI 1.621-12.677), mechanical ventilation (OR: 3.890; 95% CI 1.445-10.474) and renal replacement therapy (OR: 2.816; 95% CI 1.318-6.016) were associated with increased ICU mortality, in contrast to non-surgical source control (OR: 0.292; 95% CI 0.126-0.678) which was associated with decreased ICU mortality. Improvements are needed in the management of sepsis in Vietnam such as increasing resources in critical care settings, making accredited training programs more available, improving compliance with sepsis bundles of care, and treating underlying illness and shock optimally in septic patients.


Subject(s)
Intensive Care Units/statistics & numerical data , Sepsis/mortality , Aged , Cross-Sectional Studies , Female , Hospital Mortality , Humans , Male , Middle Aged , Risk Assessment/statistics & numerical data , Risk Factors , Sepsis/therapy , Vietnam/epidemiology
12.
Chem Commun (Camb) ; 57(75): 9518-9521, 2021 Sep 21.
Article in English | MEDLINE | ID: mdl-34486620

ABSTRACT

The NbAl8H8+ cluster was formed in a molecular beam and characterized by mass spectrometry and infrared spectroscopy. Density functional theory calculations show the lowest-energy isomer is a high symmetry singlet with the Nb atom placed at the center of a distorted hexagonal Al ring and coordinated by two AlH moieties, therefore exhibiting octacoordination. The unprecedented high-symmetric geometry is attributed to the 20 valence electrons; the central Nb atom adheres to the 18-electron rule and two additional delocalized electrons stabilize the hexagonal ring.

13.
Front Psychol ; 12: 805450, 2021.
Article in English | MEDLINE | ID: mdl-35153927

ABSTRACT

Local item dependence (LID) is one of the most critical assumption in the Rasch model when it comes to the validity of a test. As the field of vocabulary assessment is calling for more clarity and validity for vocabulary tests, such assumption becomes more important than ever. The article offers a Rasch-based investigation into the issue of LID with the focus on the two popular formats of Vocabulary Levels Tests (VLT): multiple-choice and matching. A Listening Vocabulary Levels Test (LVLT) and an Updated Vocabulary Levels Test (UVLT) were given to a single cohort of 311 university students in an English as a Foreign Language (EFL) context. The analyses of raw score and standardized residuals correlations were conducted. The findings found no relationship between the 4-option, multiple-choice format of the LVLT and item local dependence. However, results from score and standardized residuals correlations analyses showed a strong link between the 3-item-per-cluster, matching format and item local dependence. The study calls for greater attention to the format of future vocabulary tests and support the use of meaning-recall formats in vocabulary testing.

14.
RSC Adv ; 10(34): 19781-19789, 2020 May 26.
Article in English | MEDLINE | ID: mdl-35520435

ABSTRACT

A pentagonal hetero-prismatic structural motif was found for singly transition metal doped M@Ge5E5 + clusters, where the transition metal atom is located at the centre of a (5/5) Ge5E5 prism in which Ge is mixed with either P or As atoms. Structural characterization indicates that each (5/5) Ge5E5 prism is established by joining of two Ge3E2 and Ge2E3 strings in a prismatic fashion rather than two Ge5 and E5 strings. Each string results from a remarkable mixture of Ge and E atoms and contains only one E-E connection due to the fact that Ge-E bonds are much stronger than E-E connections. From the donor-acceptor perspective, the Ge5E5 tube donates electrons to the M center, which behaves as an acceptor. NBO atomic charge and ELI_D analyses demonstrate such electrostatic interactions of the M dopant with a Ge5E5 + tube which likely induce thermodynamic stability for the resulting M@Ge5E5 + cluster. CMO analysis illustrates that the conventional 18 electron count is recovered in the M@Ge5E5 + cations.

15.
J Phys Chem A ; 123(50): 10721-10729, 2019 Dec 19.
Article in English | MEDLINE | ID: mdl-31756105

ABSTRACT

Structural transformation is a unique characteristic of atomic clusters, but it turns out very different from cluster to cluster. This theoretical study proves that the isomeric transformation between hexagonal prism and hexagonal antiprism is found for the doubly doped Cr2Ge12 cluster but not for singly doped CrGe12 cluster. We confirm that the ground state of CrGe12 is the distorted hexagonal prism C2h at the 3Bg triplet state instead of various shapes predicted in the previous studies. Upon comparison between the estimation at the B3P86/6-311+G(d) level of theory and the detachment energies measured by photoelectron spectroscopy, hexagonal antiprismatic shape is identified as the most stable isomer of the Cr2Ge12 cluster and it is easy to transform to the hexagonal prism-a less stable isomer by the rotation of the hexagonal rings. That is the first evidence for the structural transformation between a hexagonal prism and an antiprism of the germanium clusters, referring to the ability of Ge-based clusters in the formation of tubular geometry by doping Cr atoms. All the low-energy isomers of both Cr-doped germanium clusters have high magnetic moments. Interestingly, there is a tuning in magnetic properties of Cr2Ge12 from the ferromagnetism of the lowest-lying hexagonal antiprism to the ferrimagnetism of the higher-energy hexagonal prism. The stronger Cr-Cr bond and stronger interaction between the Cr2 moiety and the antiprism cage are accounted for by the higher stability of the hexagonal antiprismatic isomer.

16.
Phys Chem Chem Phys ; 21(16): 8365-8375, 2019 Apr 17.
Article in English | MEDLINE | ID: mdl-30941393

ABSTRACT

A systematic investigation on structure, relative stabilities, dissociation behavior and bonding of the singly and doubly Ni doped boron clusters BnNim with n = 2-22 and m = 1-2, was carried out using density functional theory (TPSSh functional) calculations. Calculated results indicate that for n < 14, BnNim structures are generally formed by capping Ni atom(s) on the edge or the surface of the pure boron Bn frameworks. From n = 14, the Ni dopants exert stronger effects in such a way that the most stable isomers BnNim adopt the shape of the related double ring tubular boron structures. With n ≥ 20, the Bn double ring appears to possess a large enough volume to entirely enclose the Ni2 dimer. The B14Ni and B22Ni2 turn out to be remarkable species with enhanced thermodynamic stability with larger average binding energies along with surprising geometric structures. Their higher thermodynamic stability can be understood in terms of the MO energy levels predicted by a hollow cylinder model, and other electronic properties. The (2 0 2)-orbital derived from the model of particle in a hollow cylinder appears to play a key role in the stabilization of the boron double ring.

17.
Phys Chem Chem Phys ; 21(13): 7039-7044, 2019 Mar 27.
Article in English | MEDLINE | ID: mdl-30874278

ABSTRACT

The lowest-lying isomer of the B50 boron cluster is confirmed to have a quasi-planar shape with two hexagonal holes. By applying a topological (leap-frog) dual operation followed by boron capping, we demonstrated that such a quasi-planar structure actually comes from the smallest elongated B102-, and its high thermodynamic stability is due to its inherent disk aromaticity arising from its 32 valent π electrons that fully occupy a disk configuration of [(1σ)2(1π)4(1δ)4(2σ)2(1φ)4(2π)4(1γ)4(2δ)4(1η)4]. The aromatic character of the quasi-planar B50 is further supported by a strong diatropic magnetic current flow. The sudden appearance of a quasi-planar B50 again points out that the growth pattern of pure boron clusters is still far from being completely understood.

18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 2869-2872, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30441000

ABSTRACT

The aim of this present research was to determine whether the cardiovascular function has been affected by wearing compression garments during the recovery phase. Fourteen subjects (men, $\text{n}=$7; women, $\textbf{n}=$7; $24.7 \pm 4.5$ years, $166.0 \pm 7.6$ cm; $60.9 \pm 12.0$ kg) completed a running protocol on a treadmill. Each subject participated in two running experiments, using either compression garments (CGs) or non- compression garments (NCGs) during exercise and 2 hours recovering time. Electrocardiogram (ECG) signals were collected during 2 hours recovery using wearable sensors. The present work indicated a statistically significant difference between CGs and NCGs from 90 minutes recovery onwards $( \mathrm {p}<0.05)$. ECG parameters showed some significant difference in heart rate (HR), ST and corrected QT (QTc $) ( \mathrm {p}<0.05)$. Therefore, the cardiovascular function was positively influenced by the application of CGs during the recovery phase.


Subject(s)
Clothing , Running , Exercise , Exercise Test , Female , Heart Rate , Humans , Male
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 3032-3035, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30441034

ABSTRACT

The specific purpose of this present paper was to investigate whether the EEG activity has been affected by wearing whole body compression garments during a running test. Ten subjects (men, n=5; women, n=5; age: 24.11 ± 4.48 years; height: 163.56 ± 7.70 cm; chest: 87.78 ± 6.92 cm; weight: 58.67 ± 10.96 kg; BMI: 21.77 ± 2.63 kg.m-2) completed a running protocol on a treadmill. Each subject participated in two running trials, wearing either a compression garment (CG) or a non-compression garment (NCG) during exercise. Electroencephalogram (EEG) signals were collected during exercise using wearable sensors. The present study revealed a statistically significant difference between CGs and NCGs in alpha, beta and theta power spectral density (p<0.05). Therefore, the brain activity was influenced by the application of CGs during the running test. This result would also recommends an application of CGs in training as well as in competition.


Subject(s)
Electroencephalography , Adult , Clothing , Exercise , Exercise Test , Female , Humans , Male , Stockings, Compression , Young Adult
20.
Phys Chem Chem Phys ; 20(41): 26072-26082, 2018 Nov 07.
Article in English | MEDLINE | ID: mdl-30113045

ABSTRACT

The geometries, bonding and abilities for CO2 capture of the doubly rhodium-doped boron cluster Rh2B18 are presented. DFT calculations using the TPSSh functional show that the doubly doped Rh2B18 is stable in a high symmetry shape (D9d) in which two Rh dopants are vertically and oppositely coordinated to nonagonal faces of a (2 × 9) double ring B18 tube, having the form of a teetotum toy. Bonding of the tube is analysed using different schemes for partition of total electron density (EDI_D, AIM). The high thermodynamic stability of Rh2B18 can be rationalized in terms of its electron distribution in which both Rh atoms share delocalized bonds with B atoms. Molecular dynamic simulations also confirm its stability within a range of temperatures. Exploration of the interaction of gas phase CO2 molecules with Rh2B18 suggests that this tubular structure has a great ability for capture and transformation of carbon dioxide. Formation of two new strong bonds of CO2 with the B-B edges of Rh2B18 favour its capture through a dissociative adsorption mechanism in which a nearly spontaneous dissociation of CO2 into CO and BO groups follows its attachment.

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